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from functools import reduce

def fact(n):
    """
    Returns the factorial of the given positive number.
    If the given number is negative returns 0
    Inputs:
        @n: The number to calculate
    Outputs:
        The Factorial
    """
    if n > 0:
        fact_lamba = lambda x, y: x * y
        return reduce(fact_lamba, range(1,n+1))
    return 0

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