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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 get_index(lis, argument):
 """Find the index of an item, given either the item or index as an argument. Particularly useful as a wrapper for arguments like channel or axis. Parameters lis : list List to parse. argument : int or object Argument. Returns ------- int Index of chosen object. """

    # get channel
    if isinstance(argument, int):
        if -len(lis) <= argument < len(lis):
            return argument
        else:
            raise IndexError("index {0} incompatible with length {1}".format(argument, len(lis)))
    else:
        return lis.index(argument)