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Python: completed Black Jack

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{
"authors": [
"Ticktakto",
"Yabby1997",
"limm-jk",
"OMEGA-Y",
"wnstj2007",
"pranasziaukas",
"bethanyG"
],
"contributors": [
"PaulT89"
],
"files": {
"solution": [
"black_jack.py"
],
"test": [
"black_jack_test.py"
],
"exemplar": [
".meta/exemplar.py"
]
},
"icon": "poker",
"blurb": "Learn about comparisons by implementing some Black Jack judging rules."
}

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{"track":"python","exercise":"black-jack","id":"c39a445c45914cf69f9cd468976225b8","url":"https://exercism.org/tracks/python/exercises/black-jack","handle":"Chomp1295","is_requester":true,"auto_approve":false}

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# Help
## Running the tests
We use [pytest][pytest: Getting Started Guide] as our website test runner.
You will need to install `pytest` on your development machine if you want to run tests for the Python track locally.
You should also install the following `pytest` plugins:
- [pytest-cache][pytest-cache]
- [pytest-subtests][pytest-subtests]
Extended information can be found in our website [Python testing guide][Python track tests page].
### Running Tests
To run the included tests, navigate to the folder where the exercise is stored using `cd` in your terminal (_replace `{exercise-folder-location}` below with your path_).
Test files usually end in `_test.py`, and are the same tests that run on the website when a solution is uploaded.
Linux/MacOS
```bash
$ cd {path/to/exercise-folder-location}
```
Windows
```powershell
PS C:\Users\foobar> cd {path\to\exercise-folder-location}
```
<br>
Next, run the `pytest` command in your terminal, replacing `{exercise_test.py}` with the name of the test file:
Linux/MacOS
```bash
$ python3 -m pytest -o markers=task {exercise_test.py}
==================== 7 passed in 0.08s ====================
```
Windows
```powershell
PS C:\Users\foobar> py -m pytest -o markers=task {exercise_test.py}
==================== 7 passed in 0.08s ====================
```
### Common options
- `-o` : override default `pytest.ini` (_you can use this to avoid marker warnings_)
- `-v` : enable verbose output.
- `-x` : stop running tests on first failure.
- `--ff` : run failures from previous test before running other test cases.
For additional options, use `python3 -m pytest -h` or `py -m pytest -h`.
### Fixing warnings
If you do not use `pytest -o markers=task` when invoking `pytest`, you might receive a `PytestUnknownMarkWarning` for tests that use our new syntax:
```bash
PytestUnknownMarkWarning: Unknown pytest.mark.task - is this a typo? You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
```
To avoid typing `pytest -o markers=task` for every test you run, you can use a `pytest.ini` configuration file.
We have made one that can be downloaded from the top level of the Python track directory: [pytest.ini][pytest.ini].
You can also create your own `pytest.ini` file with the following content:
```ini
[pytest]
markers =
task: A concept exercise task.
```
Placing the `pytest.ini` file in the _root_ or _working_ directory for your Python track exercises will register the marks and stop the warnings.
More information on pytest marks can be found in the `pytest` documentation on [marking test functions][pytest: marking test functions with attributes] and the `pytest` documentation on [working with custom markers][pytest: working with custom markers].
Information on customizing pytest configurations can be found in the `pytest` documentation on [configuration file formats][pytest: configuration file formats].
### Extending your IDE or Code Editor
Many IDEs and code editors have built-in support for using `pytest` and other code quality tools.
Some community-sourced options can be found on our [Python track tools page][Python track tools page].
[Pytest: Getting Started Guide]: https://docs.pytest.org/en/latest/getting-started.html
[Python track tools page]: https://exercism.org/docs/tracks/python/tools
[Python track tests page]: https://exercism.org/docs/tracks/python/tests
[pytest-cache]:http://pythonhosted.org/pytest-cache/
[pytest-subtests]:https://github.com/pytest-dev/pytest-subtests
[pytest.ini]: https://github.com/exercism/python/blob/main/pytest.ini
[pytest: configuration file formats]: https://docs.pytest.org/en/6.2.x/customize.html#configuration-file-formats
[pytest: marking test functions with attributes]: https://docs.pytest.org/en/6.2.x/mark.html#raising-errors-on-unknown-marks
[pytest: working with custom markers]: https://docs.pytest.org/en/6.2.x/example/markers.html#working-with-custom-markers
## Submitting your solution
You can submit your solution using the `exercism submit black_jack.py` command.
This command will upload your solution to the Exercism website and print the solution page's URL.
It's possible to submit an incomplete solution which allows you to:
- See how others have completed the exercise
- Request help from a mentor
## Need to get help?
If you'd like help solving the exercise, check the following pages:
- The [Python track's documentation](https://exercism.org/docs/tracks/python)
- The [Python track's programming category on the forum](https://forum.exercism.org/c/programming/python)
- [Exercism's programming category on the forum](https://forum.exercism.org/c/programming/5)
- The [Frequently Asked Questions](https://exercism.org/docs/using/faqs)
Should those resources not suffice, you could submit your (incomplete) solution to request mentoring.
Below are some resources for getting help if you run into trouble:
- [The PSF](https://www.python.org) hosts Python downloads, documentation, and community resources.
- [The Exercism Community on Discord](https://exercism.org/r/discord)
- [Python Community on Discord](https://pythondiscord.com/) is a very helpful and active community.
- [/r/learnpython/](https://www.reddit.com/r/learnpython/) is a subreddit designed for Python learners.
- [#python on Libera.chat](https://www.python.org/community/irc/) this is where the core developers for the language hang out and get work done.
- [Python Community Forums](https://discuss.python.org/)
- [Free Code Camp Community Forums](https://forum.freecodecamp.org/)
- [CodeNewbie Community Help Tag](https://community.codenewbie.org/t/help)
- [Pythontutor](http://pythontutor.com/) for stepping through small code snippets visually.
Additionally, [StackOverflow](http://stackoverflow.com/questions/tagged/python) is a good spot to search for your problem/question to see if it has been answered already.
If not - you can always [ask](https://stackoverflow.com/help/how-to-ask) or [answer](https://stackoverflow.com/help/how-to-answer) someone else's question.

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# Hints
[The Python comparisons tutorial][python comparisons tutorial] and [Python comparisons examples][python comparisons examples] are a great introduction covering the content of this exercise.
## 1. Calculate the value of a card
- You can use the equality comparison operator `==` to determine if a card is an ace card: `card == 'A'`.
- You can use the containment operator `in` to determine if a substring is contained inside a string: `'Q' in 'KJQ'`.
- You can use the [`int` constructor][int constructor] to convert a `str` of an `int` to an `int`: `int('13')`.
## 2. Determine which card has a higher value
- Once you have defined the `value_of_card` function, you can call it from other functions.
- You can use the value comparison operators `>` and `<` to determine if specific cards are _greater than_ or _less than_ a given value: `3 < 12`.
- You can use the equality comparison operator `==` to determine if two values are equal to one another.
## 3. Calculate the value of an ace
- Once you have defined the `value_of_card` function, you can call it from other functions.
- You can use the order comparison operator `>` to decide the appropriate course of action here.
## 4. Determine Blackjack
- Remember, you can use the [`if`/`elif`/`else` syntax][if syntax] to handle different combinations of cards.
- You can chain BOTH comparison operators and boolean operators _arbitrarily_: `y < z < x` or `(y or z) and (x or z)`
- You can reuse the already implemented `value_of_card` function.
## 5. Splitting pairs
- You can reuse the already implemented `value_of_card` function.
- You can handle the `A` case (when at least one of the cards in an ace) separately.
## 6. Doubling down
- An `A` scored at 11 will never allow doubling down if there are two cards in the hand.
- Given the first point, you _should_ be able to reuse the already implemented `value_of_card` function.
- You can chain comparison operators _arbitrarily_: `y < z < x`.
- You can use the [conditional expression][conditional expression] (_sometimes called a "ternary operator"_)
to shorten simple `if`/`else` statements: `13 if letter == 'M' else 3`.
[conditional expression]: https://docs.python.org/3/reference/expressions.html#conditional-expressions
[if syntax]: https://docs.python.org/3/tutorial/controlflow.html#if-statements
[int constructor]: https://docs.python.org/3/library/functions.html#int
[python comparisons examples]: https://www.tutorialspoint.com/python/comparison_operators_example.htm
[python comparisons tutorial]: https://docs.python.org/3/reference/expressions.html#comparisons

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# Black Jack
Welcome to Black Jack on Exercism's Python Track.
If you need help running the tests or submitting your code, check out `HELP.md`.
If you get stuck on the exercise, check out `HINTS.md`, but try and solve it without using those first :)
## Introduction
## Comparisons
Python supports the following basic comparison operators:
| Operator | Operation | Description |
| -------- | -------------------------- | ------------------------------------------------------------------------- |
| `>` | "greater than" | `a > b` is `True` if `a` is **strictly** greater in value than `b` |
| `<` | "less than" | `a < b` is `True` if `a` is **strictly** less in value than `b` |
| `==` | "equal to" | `a == b` is `True` if `a` is **strictly** equal to `b` in value |
| `>=` | "greater than or equal to" | `a >= b` is `True` if `a > b` OR `a == b` in value |
| `<=` | "less than or equal to" | `a <= b` is `True` if `a < b` or `a == b` in value |
| `!=` | "not equal to" | `a != b` is `True` if `a == b` is `False` |
| `is` | "identity" | `a is b` is `True` if **_and only if_** `a` and `b` are the same _object_ |
| `is not` | "negated identity" | `a is not b` is `True` if `a` and `b` are **not** the same _object_ |
| `in` | "containment test" | `a in b` is `True` if `a` is member, subset, or element of `b` |
| `not in` | "negated containment test" | `a not in b` is `True` if `a` is not a member, subset, or element of `b` |
They all have the same priority (_which is higher than that of [Boolean operations][boolean operations], but lower than that of arithmetic or bitwise operations_).
## Comparison between different data types
Objects that are different types (_except numeric types_) never compare equal by default.
Non-identical instances of a `class` will also _**not**_ compare as equal unless the `class` defines special [rich comparison][rich comparisons] methods that customize the default `object` comparison behavior.
Customizing via `rich comparisons` will be covered in a follow-on exercise.
For (much) more detail on this topic, see [Value comparisons][value comparisons] in the Python documentation.
Numeric types are (mostly) an exception to this type matching rule.
An `integer` **can** be considered equal to a `float` (_or an [`octal`][octal] equal to a [`hexadecimal`][hex]_), as long as the types can be implicitly converted for comparison.
For the other numeric types in the Python standard library ([complex][complex numbers], [decimal][decimal numbers], [fractions][rational numbers]), comparison operators are defined where they "make sense" (_where implicit conversion does not change the outcome_), but throw a `TypeError` if the underlying objects cannot be accurately converted for comparison.
For more information on the rules that python uses for _numeric conversion_, see [arithmetic conversions][arithmetic conversions] in the Python documentation.
```python
>>> import fractions
# A string cannot be converted to an int.
>>> 17 == '17'
False
# An int can be converted to float for comparison.
>>> 17 == 17.0
True
# The fraction 6/3 can be converted to the int 2
# The int 2 can be converted to 0b10 in binary.
>>> 6/3 == 0b10
True
# An int can be converted to a complex number with a 0 imaginary part.
>>> 17 == complex(17)
True
# The fraction 2/5 can be converted to the float 0.4
>>> 0.4 == 2/5
True
>>> complex(2/5, 1/2) == complex(0.4, 0.5)
True
```
Any ordered comparison of a number to a `NaN` (_not a number_) type is `False`.
A confusing side effect of Python's `NaN` definition is that `NaN` never compares equal to `NaN`.
```python
>>> x = float('NaN')
>>> 3 < x
False
>>> x < 3
False
# NaN never compares equal to NaN
>>> x == x
False
```
## Comparing Strings
Unlike numbers, strings (`str`) are compared [_lexicographically_][lexographic order], using their individual Unicode code points (_the result of passing each code point in the `str` to the built-in function [`ord()`][ord], which returns an `int`_).
If all code points in both strings match and are _**in the same order**_, the two strings are considered equal.
This comparison is done in a 'pair-wise' fashion - first-to-first, second-to-second, etc.
In Python 3.x, `str` and `bytes` cannot be directly coerced/compared.
```python
>>> 'Python' > 'Rust'
False
>>> 'Python' > 'JavaScript'
True
# Examples with Mandarin.
# hello < goodbye
>>> '你好' < '再见'
True
# ord() of first characters
>>> ord('你'), ord('再')
(20320, 20877)
# ord() of second characters
>>> ord('好'), ord('见')
(22909, 35265)
# And with Korean words.
# Pretty < beautiful.
>>> '예쁜' < '아름다운'
False
>>> ord('예'), ord('아')
(50696, 50500)
```
## Comparison Chaining
Comparison operators can be chained _arbitrarily_ -- meaning that they can be used in any combination of any length.
Note that the evaluation of an expression takes place from `left` to `right`.
As an example, `x < y <= z` is equivalent to `x < y` `and` `y <= z`, except that `y` is evaluated **only once**.
In both cases, `z` is _not_ evaluated **at all** when `x < y` is found to be `False`.
This is often called `short-circuit evaluation` - the evaluation stops if the truth value of the expression has already been determined.
`Short circuiting` is supported by various boolean operators, functions, and also by comparison chaining in Python.
Unlike many other programming languages, including `C`, `C++`, `C#`, and `Java`, chained expressions like `a < b < c` in Python have a conventional [mathematical interpretation][three way boolean comparison] and precedence.
```python
>>> x = 2
>>> y = 5
>>> z = 10
>>> x < y < z
True
>>> x < y > z
False
>>> x > y < z
False
```
## Comparing object identity
The operators `is` and `is not` test for object [_identity_][object identity], as opposed to object _value_.
An object's identity never changes after creation and can be found by using the [`id()`][id function] function.
`<apple> is <orange>` evaluates to `True` if _**and only if**_ `id(<apple>)` == `id(<orange>)`.
`<apple> is not <orange>` yields the inverse.
Due to their singleton status, `None` and `NotImplemented` should always be compared to items using `is` and `is not`.
See the Python reference docs on [value comparisons][value comparisons none] and [PEP8][pep8 programming recommendations] for more details on this convention.
```python
>>> my_fav_numbers = [1, 2, 3]
>>> your_fav_numbers = my_fav_numbers
>>> my_fav_numbers is your_fav_numbers
True
# The returned id will differ by system and python version.
>>> id(my_fav_numbers)
4517478208
# your_fav_numbers is only an alias pointing to the original my_fav_numbers object.
# Assigning a new name does not create a new object.
>>> id(your_fav_numbers)
4517478208
>>> my_fav_numbers is not your_fav_numbers
False
>>> my_fav_numbers is not None
True
>>> my_fav_numbers is NotImplemented
False
```
## Membership comparisons
The operators `in` and `not in` test for _membership_.
`<fish> in <soup>` evaluates to `True` if `<fish>` is a member of `<soup>` (_if `<fish>` is a subset of or is contained within `<soup>`_), and evaluates `False` otherwise.
`<fish> not in <soup>` returns the negation, or _opposite of_ `<fish> in <soup>`.
For string and bytes types, `<name> in <fullname>` is `True` _**if and only if**_ `<name>` is a substring of `<fullname>`.
```python
# A set of lucky numbers.
>>> lucky_numbers = {11, 22, 33}
>>> 22 in lucky_numbers
True
>>> 44 in lucky_numbers
False
# A dictionary of employee information.
>>> employee = {'name': 'John Doe',
'id': 67826, 'age': 33,
'title': 'ceo'}
# Checking for the membership of certain keys.
>>> 'age' in employee
True
>>> 33 in employee
False
>>> 'lastname' not in employee
True
# Checking for substring membership
>>> name = 'Super Batman'
>>> 'Bat' in name
True
>>> 'Batwoman' in name
False
```
[arithmetic conversions]: https://docs.python.org/3/reference/expressions.html?highlight=number%20conversion#arithmetic-conversions
[boolean operations]: https://docs.python.org/3/library/stdtypes.html#boolean-operations-and-or-not
[complex numbers]: https://docs.python.org/3/library/functions.html#complex
[decimal numbers]: https://docs.python.org/3/library/decimal.html
[hex]: https://docs.python.org/3/library/functions.html?highlight=hex#hex
[id function]: https://docs.python.org/3/library/functions.html#id
[lexographic order]: https://en.wikipedia.org/wiki/Lexicographic_order
[object identity]: https://docs.python.org/3/reference/datamodel.html
[octal]: https://docs.python.org/3/library/functions.html?#oct
[ord]: https://docs.python.org/3/library/functions.html#ord
[pep8 programming recommendations]: https://pep8.org/#programming-recommendations
[rational numbers]: https://docs.python.org/3/library/fractions.html
[rich comparisons]: https://docs.python.org/3/reference/datamodel.html#object.__lt__
[three way boolean comparison]: https://en.wikipedia.org/wiki/Three-way_comparison
[value comparisons none]: https://docs.python.org/3/reference/expressions.html?highlight=none#value-comparisons
[value comparisons]: https://docs.python.org/3/reference/expressions.html?highlight=nan#value-comparisons
## Instructions
In this exercise you are going to implement some rules of [Blackjack][blackjack],
such as the way the game is played and scored.
**Note** : In this exercise, _`A`_ means ace, _`J`_ means jack, _`Q`_ means queen, and _`K`_ means king.
Jokers are discarded.
A [standard French-suited 52-card deck][standard_deck] is assumed, but in most versions, several decks are shuffled together for play.
## 1. Calculate the value of a card
In Blackjack, it is up to each individual player if an ace is worth 1 or 11 points (_more on that later_).
Face cards (`J`, `Q`, `K`) are scored at 10 points and any other card is worth its "pip" (_numerical_) value.
Define the `value_of_card(<card>)` function with parameter `card`.
The function should return the _numerical value_ of the passed-in card string.
Since an ace can take on multiple values (1 **or** 11), this function should fix the value of an ace card at 1 for the time being.
Later on, you will implement a function to determine the value of an ace card, given an existing hand.
```python
>>> value_of_card('K')
10
>>> value_of_card('4')
4
>>> value_of_card('A')
1
```
## 2. Determine which card has a higher value
Define the `higher_card(<card_one>, <card_two>)` function having parameters `card_one` and `card_two`.
For scoring purposes, the value of `J`, `Q` or `K` is 10.
The function should return which card has the higher value for scoring.
If both cards have an equal value, return both.
Returning both cards can be done by using a comma in the `return` statement:
```python
# Using a comma in a return creates a Tuple. Tuples will be covered in a later exercise.
>>> def returning_two_values(value_one, value_two):
return value_one, value_two
>>> returning_two_values('K', '3')
('K', '3')
```
An ace can take on multiple values, so we will fix `A` cards to a value of 1 for this task.
```python
>>> higher_card('K', '10')
('K', '10')
>>> higher_card('4', '6')
'6'
>>> higher_card('K', 'A')
'K'
```
## 3. Calculate the value of an ace
As mentioned before, an ace can be worth _either_ 1 **or** 11 points.
Players try to get as close as possible to a score of 21, without going _over_ 21 (_going "bust"_).
Define the `value_of_ace(<card_one>, <card_two>)` function with parameters `card_one` and `card_two`, which are a pair of cards already in the hand _before_ getting an ace card.
Your function will have to decide if the upcoming ace will get a value of 1 or a value of 11, and return that value.
Remember: the value of the hand with the ace needs to be as high as possible _without_ going over 21.
**Hint**: if we already have an ace in hand, then the value for the upcoming ace would be 1.
```python
>>> value_of_ace('6', 'K')
1
>>> value_of_ace('7', '3')
11
```
## 4. Determine a "Natural" or "Blackjack" Hand
If a player is dealt an ace (`A`) and a ten-card (10, `K`, `Q`, or `J`) as their first two cards, then the player has a score of 21.
This is known as a **blackjack** hand.
Define the `is_blackjack(<card_one>, <card_two>)` function with parameters `card_one` and `card_two`, which are a pair of cards.
Determine if the two-card hand is a **blackjack**, and return the boolean `True` if it is, `False` otherwise.
**Note** : The score _calculation_ can be done in many ways.
But if possible, we'd like you to check if there is an ace and a ten-card **_in_** the hand (_or at a certain position_), as opposed to _summing_ the hand values.
```python
>>> is_blackjack('A', 'K')
True
>>> is_blackjack('10', '9')
False
```
## 5. Splitting pairs
If the players first two cards are of the same value, such as two sixes, or a `Q` and `K` a player may choose to treat them as two separate hands.
This is known as "splitting pairs".
Define the `can_split_pairs(<card_one>, <card_two>)` function with parameters `card_one` and `card_two`, which are a pair of cards.
Determine if this two-card hand can be split into two pairs.
If the hand can be split, return the boolean `True` otherwise, return `False`
```python
>>> can_split_pairs('Q', 'K')
True
>>> can_split_pairs('10', 'A')
False
```
## 6. Doubling down
When the original two cards dealt total 9, 10, or 11 points, a player can place an additional bet equal to their original bet.
This is known as "doubling down".
Define the `can_double_down(<card_one>, <card_two>)` function with parameters `card_one` and `card_two`, which are a pair of cards.
Determine if the two-card hand can be "doubled down", and return the boolean `True` if it can, `False` otherwise.
```python
>>> can_double_down('A', '9')
True
>>> can_double_down('10', '2')
False
```
[blackjack]: https://bicyclecards.com/how-to-play/blackjack/
[standard_deck]: https://en.wikipedia.org/wiki/Standard_52-card_deck
## Source
### Created by
- @Ticktakto
- @Yabby1997
- @limm-jk
- @OMEGA-Y
- @wnstj2007
- @pranasziaukas
- @bethanyG
### Contributed to by
- @PaulT89

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"""Functions to help play and score a game of blackjack.
How to play blackjack: https://bicyclecards.com/how-to-play/blackjack/
"Standard" playing cards: https://en.wikipedia.org/wiki/Standard_52-card_deck
"""
def value_of_card(card):
"""Determine the scoring value of a card.
:param card: str - given card.
:return: int - value of a given card. See below for values.
1. 'J', 'Q', or 'K' (otherwise known as "face cards") = 10
2. 'A' (ace card) = 1
3. '2' - '10' = numerical value.
"""
res = 0
if card >= "J":
res = 10
elif card == "A":
res = 1
else:
res = int(card)
return res
def higher_card(card_one, card_two):
"""Determine which card has a higher value in the hand.
:param card_one, card_two: str - cards dealt in hand. See below for values.
:return: str or tuple - resulting Tuple contains both cards if they are of equal value.
1. 'J', 'Q', or 'K' (otherwise known as "face cards") = 10
2. 'A' (ace card) = 1
3. '2' - '10' = numerical value.
"""
card_one_val = value_of_card(card_one)
card_two_val = value_of_card(card_two)
if card_one_val == card_two_val:
return (card_one, card_two)
if card_one_val > card_two_val:
return card_one
return card_two
def value_of_ace(card_one, card_two):
"""Calculate the most advantageous value for the ace card.
:param card_one, card_two: str - card dealt. See below for values.
:return: int - either 1 or 11 value of the upcoming ace card.
1. 'J', 'Q', or 'K' (otherwise known as "face cards") = 10
2. 'A' (ace card) = 11 (if already in hand)
3. '2' - '10' = numerical value.
"""
if (value_of_card(card_one) + value_of_card(card_two) >= 11) or "A" in (
card_one,
card_two,
):
return 1
return 11
def is_blackjack(card_one, card_two):
"""Determine if the hand is a 'natural' or 'blackjack'.
:param card_one, card_two: str - card dealt. See below for values.
:return: bool - is the hand is a blackjack (two cards worth 21).
1. 'J', 'Q', or 'K' (otherwise known as "face cards") = 10
2. 'A' (ace card) = 11 (if already in hand)
3. '2' - '10' = numerical value.
"""
if card_one != "A" and card_two != "A":
return False
if card_one == "A":
return value_of_card(card_two) + 11 == 21
return value_of_card(card_one) + 11 == 21
def can_split_pairs(card_one, card_two):
"""Determine if a player can split their hand into two hands.
:param card_one, card_two: str - cards dealt.
:return: bool - can the hand be split into two pairs? (i.e. cards are of the same value).
"""
return value_of_card(card_one) == value_of_card(card_two)
def can_double_down(card_one, card_two):
"""Determine if a blackjack player can place a double down bet.
:param card_one, card_two: str - first and second cards in hand.
:return: bool - can the hand can be doubled down? (i.e. totals 9, 10 or 11 points).
"""
return 9 <= value_of_card(card_one) + value_of_card(card_two) <= 11

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import unittest
import pytest
from black_jack import (
value_of_card,
higher_card,
value_of_ace,
is_blackjack,
can_split_pairs,
can_double_down
)
class BlackJackTest(unittest.TestCase):
@pytest.mark.task(taskno=1)
def test_value_of_card(self):
test_data = [('2', 2), ('5', 5), ('8', 8),
('A', 1), ('10', 10), ('J', 10),
('Q', 10), ('K', 10)]
for variant, (card, expected) in enumerate(test_data, 1):
with self.subTest(f'variation #{variant}', card=card, expected=expected):
actual_result = value_of_card(card)
error_msg = (f'Called value_of_card({card}). '
f'The function returned {actual_result} as the value of the {card} card, '
f'but the test expected {expected} as the {card} card value.')
self.assertEqual(actual_result, expected, msg=error_msg)
@pytest.mark.task(taskno=2)
def test_higher_card(self):
test_data = [('A', 'A', ('A', 'A')),
('10', 'J', ('10', 'J')),
('3', 'A', '3'),
('3', '6', '6'),
('Q', '10', ('Q', '10')),
('4', '4', ('4', '4')),
('9', '10', '10'),
('6', '9', '9'),
('4', '8', '8')]
for variant, (card_one, card_two, expected) in enumerate(test_data, 1):
with self.subTest(f'variation #{variant}', card_one=card_one, card_two=card_two, expected=expected):
actual_result = higher_card(card_one, card_two)
error_msg = (f'Called higher_card({card_one}, {card_two}). '
f'The function returned {actual_result}, '
f'but the test expected {expected} as the result for the cards {card_one, card_two}.')
self.assertEqual(actual_result, expected, msg=error_msg)
@pytest.mark.task(taskno=3)
def test_value_of_ace(self):
test_data = [('2', '3', 11), ('3', '6', 11), ('5', '2', 11),
('8', '2', 11), ('5', '5', 11), ('Q', 'A', 1),
('10', '2', 1), ('7', '8', 1), ('J', '9', 1),
('K', 'K', 1), ('2', 'A', 1), ('A', '2', 1)]
for variant, (card_one, card_two, ace_value) in enumerate(test_data, 1):
with self.subTest(f'variation #{variant}', card_one=card_one, card_two=card_two, ace_value=ace_value):
actual_result = value_of_ace(card_one, card_two)
error_msg = (f'Called value_of_ace({card_one}, {card_two}). '
f'The function returned {actual_result}, '
f'but the test expected {ace_value} as the value of an ace card '
f'when the hand includes {card_one, card_two}.')
self.assertEqual(value_of_ace(card_one, card_two), ace_value, msg=error_msg)
@pytest.mark.task(taskno=4)
def test_is_blackjack(self):
test_data = [(('A', 'K'), True), (('10', 'A'), True),
(('10', '9'), False), (('A', 'A'), False),
(('4', '7'), False), (('9', '2'), False),
(('Q', 'K'), False)]
for variant, (hand, expected) in enumerate(test_data, 1):
with self.subTest(f'variation #{variant}', hand=hand, expected=expected):
actual_result = is_blackjack(*hand)
error_msg = (f'Called is_blackjack({hand[0]}, {hand[1]}). '
f'The function returned {actual_result}, '
f'but hand {hand} {"is" if expected else "is not"} a blackjack.')
self.assertEqual(actual_result, expected, msg=error_msg)
@pytest.mark.task(taskno=5)
def test_can_split_pairs(self):
test_data = [(('Q', 'K'), True), (('6', '6'), True),
(('A', 'A'), True),(('10', 'A'), False),
(('10', '9'), False)]
for variant, (hand, expected) in enumerate(test_data, 1):
with self.subTest(f'variation #{variant}', input=hand, expected=expected):
actual_result = can_split_pairs(*hand)
error_msg = (f'Called can_split_pairs({hand[0]}, {hand[1]}). '
f'The function returned {actual_result}, '
f'but hand {hand} {"can" if expected else "cannot"} be split into pairs.')
self.assertEqual(actual_result, expected, msg=error_msg)
@pytest.mark.task(taskno=6)
def test_can_double_down(self):
test_data = [(('A', '9'), True), (('K', 'A'), True),
(('4', '5'), True),(('A', 'A'), False),
(('10', '2'), False), (('10', '9'), False)]
for variant, (hand, expected) in enumerate(test_data, 1):
with self.subTest(f'variation #{variant}', hand=hand, expected=expected):
actual_result = can_double_down(*hand)
error_msg = (f'Called can_double_down({hand[0]}, {hand[1]}). '
f'The function returned {actual_result}, '
f'but hand {hand} {"can" if expected else "cannot"} be doubled down.')
self.assertEqual(actual_result, expected, msg=error_msg)