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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 polygen(*coefficients):
    '''Polynomial generating function'''
    if not coefficients:
        return lambda i: 0
    else:
        c0 = coefficients[0]
        coefficients = coefficients[1:]

        def _(i):
            v = c0
            for c in coefficients:
                v += c*i
                i *= i
            return v

        return _