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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 intersperse(lis, value):
 """Put value between each existing item in list. Parameters lis : list List to intersperse. value : object Value to insert. Returns ------- list interspersed list """

    out = [value] * (len(lis) * 2 - 1)
    out[0::2] = lis
    return out