diff --git a/.github/workflows/python-tests.yml b/.github/workflows/python-tests.yml
new file mode 100644
index 0000000..e5ac276
--- /dev/null
+++ b/.github/workflows/python-tests.yml
@@ -0,0 +1,32 @@
+name: Run Python Tests
+
+on:
+  pull_request:
+    branches:
+      - main
+  workflow_dispatch:
+  
+
+jobs:
+  test:
+    name: Test
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version: '3.x'
+        cache: 'pip'
+    - name: Install pytest
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install pytest
+    - name: Run tests
+      run: |
+        pytest -q code-challenges
+      env:
+        CI: true
+
+
diff --git a/.gitignore b/.gitignore
index 0235aaa..3661cbc 100644
--- a/.gitignore
+++ b/.gitignore
@@ -227,5 +227,11 @@ $RECYCLE.BIN/
 # Visual Studio 2015/2017 cache/options directory
 .vs/
 
+# Python
+__pycache__/
+.pytest_cache/
+*.py[cod]
+.venv/
+.coverage
+.mypy_cache/
 
-# End of https://www.gitignore.io/api/node,macos,linux,windows,webstorm,visualstudiocode
diff --git a/README.md b/README.md
index 5ec978a..961b788 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,68 @@
 # Data Structures and Algorithms
 
-## 301 Code Challenges
+### JavaScript Setup
+
+Use Node.js LTS and Yarn (recommended) to install and run tests.
+
+Node setup (optional, via nvm):
+```bash
+nvm install --lts
+nvm use --lts
+node -v
+```
+
+Install dependencies and run tests (Yarn):
+```bash
+cd <root>
+yarn
+yarn test
+```
+
+If Yarn is not available:
+```bash
+# Option A: use Corepack to activate the repo-pinned Yarn 1.x
+corepack enable
+corepack prepare yarn@1.22.22 --activate
+
+# Option B: install globally (classic Yarn)
+npm i -g yarn
+```
+
+Using npm instead of Yarn:
+```bash
+npm ci
+npm test
+```
+
+Handy commands:
+- Run a specific Jest test file: `yarn test code-challenges/challenges-01.test.js`
+- Lint JavaScript: `yarn lint`
+
+### Python Setup
+
+Set up a local Python environment and run tests:
+
+```bash
+cd /Users/tomm/repos/data-structures-and-algorithms
+python3 -m venv .venv
+source .venv/bin/activate
+python -m pip install -U pip pytest
+pytest --version
+```
+
+Run tests:
+- All Python challenges: `pytest -q code-challenges`
+- Single file: `pytest -q code-challenges/challenges_01_test.py`
+
+Pytest test discovery:
+- Default patterns: `test_*.py` or `*_test.py`
+- If you prefer “.test.py” names, add a `pytest.ini` at the repo root:
+  ```
+  [pytest]
+  python_files = *.test.py test_*.py *_test.py
+  ```
+
+## 301 Code Challenges (JavaScript)
 
 [forEach](code-challenges/challenges-01.test.js)
 
@@ -55,15 +117,6 @@
 
 [Tree Intersection](javascript/trees/binary-tree/tree-intersection/README.md)
 
-
 ### Misc
 
-[JavaScript Folder Setup](javascript/README.md)
-
-### Sources
-
-[301 Setup Instructions](https://codefellows.github.io/setup-guide/code-301/3-code-challenges)
-
-
-
-
+[JavaScript Folder Setup](javascript/README.md)
\ No newline at end of file
diff --git a/code-challenges/challenges_01_test.py b/code-challenges/challenges_01_test.py
new file mode 100644
index 0000000..15c3350
--- /dev/null
+++ b/code-challenges/challenges_01_test.py
@@ -0,0 +1,199 @@
+'''
+------------------------------------------------------------------------------------------------
+CHALLENGE 1
+
+Write a function named `addOne` that takes an array of numbers, and returns a new array of the numbers, incremented by 1.
+
+Use `forLoop` to loop over the input array and work with each value.  Push the new value into a local array. Return the local array;
+------------------------------------------------------------------------------------------------
+'''
+
+def addOne(arr):
+    result = []
+    for num in arr:
+        result.append(num + 1)
+    return result
+
+'''
+CHALLENGE 2
+
+Write a function named `addExclamation` that takes an array of strings, and returns a new array of the same strings with an "!" added to the end.
+
+Use `forLoop` to loop over the input array. Modify each string, and add the updated value into a local array. Return the local array;
+'''
+
+def addExclamation(arr):
+    result = []
+    for string in arr:
+        result.append(string + '!')
+    return result
+
+'''
+------------------------------------------------------------------------------------------------
+CHALLENGE 3
+
+Write a function named `allUpperCase` that takes an array of strings, and returns a new array of the strings converted to upper case.
+
+Use `forLoop` to loop over the input array. The modified strings should each be added into a local array. Return that local array.
+------------------------------------------------------------------------------------------------
+'''
+
+def allUpperCase(arr):
+    result = []
+    for string in arr:
+        result.append(string.upper())
+    return result
+
+'''
+------------------------------------------------------------------------------------------------
+CHALLENGE 4
+
+Write a function named `greeting` that takes in a single string and returns the string in all uppercase letters, and followed by an "!".
+
+Then, write a function named `speaker` that takes in an array of strings and a callback function.
+
+Use `forLoop` to build a new array of strings, each string modified by the callback. Return the new array.
+------------------------------------------------------------------------------------------------
+'''
+
+def greeting(word):
+    return word.upper() + '!'
+
+def speaker(words, callback):
+    result = []
+    for word in words:
+        result.append(callback(word))
+    return result
+
+'''
+------------------------------------------------------------------------------------------------
+CHALLENGE 5
+
+Write a function named addValues that takes in an array and a value and pushes the value into the array. This function does not need a return statement.
+
+Then, write a function named addNumbers that takes in four arguments:
+  - A number to be added to an array
+  - An array into which the number should be added
+  - The number of times the number should be added
+  - A callback function to use to add the numbers to the array (Hint: you already defined it)
+
+Within the addNumbers function, invoke the callback function as many times as necessary, based on the third argument of the addNumbers function.
+
+Return the modified array.
+------------------------------------------------------------------------------------------------
+'''
+
+def addValues(arr, value):
+    arr.append(value)
+
+def addNumbers(num, arr, times, callback):
+    for i in range(times):
+        callback(arr, num)
+    return arr
+
+'''
+------------------------------------------------------------------------------------------------
+
+CHALLENGE 6
+
+Write a function named createList that takes in an array of the current store inventory.
+
+The inventory is formatted like this:
+[
+  { name: 'apples', available: true },
+  { name: 'pears', available: true },
+  { name: 'oranges', available: false },
+  { name: 'bananas', available: true },
+  { name: 'blueberries', available: false }
+]
+
+This function should use forEach to populate your grocery list based on the store's inventory. If the item is available, add it to your list. Return the final list.
+------------------------------------------------------------------------------------------------
+'''
+
+def createList(availableItems):
+    result = []
+    for item in availableItems:
+        if item['available']:
+            result.append(item['name'])
+    return result
+
+'''
+------------------------------------------------------------------------------------------------
+STRETCH - CHALLENGE 7
+
+Write a function named fizzbuzz that takes in an array of numbers.
+
+Iterate over the array using forEach to determine the output based on several rules:
+  - If a number is divisible by 3, add the word "Fizz" to the output array.
+  - If the number is divisible by 5, add the word "Buzz" to the output array.
+  - If the number is divisible by both 3 and 5, add the phrase "Fizz Buzz" to the output array.
+  - Otherwise, add the number to the output array.
+
+Return the resulting output array.
+------------------------------------------------------------------------------------------------
+'''
+
+def fizzbuzz(arr):
+    result = []
+    for num in arr:
+        if num % 3 == 0 and num % 5 == 0:
+            result.append('Fizz Buzz')
+        elif num % 3 == 0:
+            result.append('Fizz')
+        elif num % 5 == 0:
+            result.append('Buzz')
+        else:
+            result.append(num)
+    return result
+
+'''
+TESTS
+
+All the code below will verify that your functions are working to solve the challenges.
+
+DO NOT CHANGE any of the below code.
+
+Run your tests with pytest:
+  - Directly (works even if filename doesn't match default discovery):
+      pytest -q code-challenges/challenges-01.test.py
+  - Or configure discovery (optional). Create a pytest.ini with:
+      [pytest]
+      python_files = *.test.py
+'''
+
+def test_add_one():
+    assert addOne([1, 2, 3, 4, 5]) == [2, 3, 4, 5, 6]
+
+def test_add_exclamation():
+    assert addExclamation(['hi', 'how', 'are', 'you']) == ['hi!', 'how!', 'are!', 'you!']
+
+def test_all_upper_case():
+    assert allUpperCase(['hi', 'how', 'are', 'you']) == ['HI', 'HOW', 'ARE', 'YOU']
+
+def test_speaker_with_greeting():
+    assert speaker(['hello', '301', 'students'], greeting) == ['HELLO!', '301!', 'STUDENTS!']
+
+def test_add_numbers():
+    result = addNumbers(8, [], 5, addValues)
+    assert result == [8, 8, 8, 8, 8]
+    assert len(result) == 5
+
+def test_create_list():
+    inventory = [
+        { 'name': 'apples', 'available': True },
+        { 'name': 'pears', 'available': True },
+        { 'name': 'oranges', 'available': False },
+        { 'name': 'bananas', 'available': True },
+        { 'name': 'blueberries', 'available': False },
+    ]
+    result = createList(inventory)
+    assert result == ['apples', 'pears', 'bananas']
+    assert len(result) == 3
+
+def test_fizzbuzz():
+    inputs = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16]
+    expected = [1, 2, 'Fizz', 4, 'Buzz', 'Fizz', 7, 8, 'Fizz', 'Buzz', 11, 'Fizz', 13, 14, 'Fizz Buzz', 16]
+    result = fizzbuzz(inputs)
+    assert result == expected
+    assert len(result) == 16
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..cf1e381
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1,3 @@
+pytest>=9,<10
+
+