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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def multiply(a, b):
    """Complete the function that takes two integers and returns the product of their unit digits. Assume the input is always valid. multiply(148, 412) should return 16. multiply(19, 28) should return 72. multiply(2020, 1851) should return 0. multiply(14,-15) should return 20. """
    return abs(a % 10) * abs(b % 10)
