code.py

import numpy as np

def sum_numbers(x, y):
    """
    TODO: IMPLEMENT ME
    Sum two numbers.

    Args:
        x (int, float): first number in sum
        y (int, float): second number in sum
    Returns:
        Sum of x and y.
    """
    # replace the following line with an actual implementation that returns something
    raise NotImplementedError()

def multiply_numbers(x, y):
    """
    TODO: IMPLEMENT ME
    Multiply two numbers.

    Args:
        x (int, float): first number in product
        y (int, float): second number in product
    Returns:
        Product of x and y.
    """
    
    # replace the following line with an actual implementation that returns something
    raise NotImplementedError()

def create_add_matrix(x):
    """
    TODO: IMPLEMENT ME
    Step 1. Create a 3x3 numpy array whose elements are all ones.
    Step 2. Sum the array and the input array x.
    Step 3. Return the result
    
    Args:
        x (np.ndarray): a 2D numpy array
    Returns:
        output (np.ndarray): the operation result
    """

    # replace the following line with an actual implementation that returns something
    raise NotImplementedError()

def indexing_aggregation(x, n):
    """
    TODO: IMPLEMENT ME
    Return the mean value of the first n elements of the input array x.

    Args:
        x (np.ndarray): a 1D numpy array
    Returns:
        output (float): the operation result

    """
    # replace the following line with an actual implementation that returns something
    raise NotImplementedError