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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 product(sequence, initial=1):
 """like the built-in sum, but for multiplication."""

    if not isinstance(sequence, collections.Iterable):
        raise TypeError("'{}' object is not iterable".format(type(sequence).__name__))

    return reduce(operator.mul, sequence, initial)