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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 remove_not_allowed_chars(savepath):
 """ Removes invalid filepath characters from the savepath. :param str savepath: the savepath to work on :return str: the savepath without invalid filepath characters """

        split_savepath = os.path.splitdrive(savepath)
        # https://msdn.microsoft.com/en-us/library/aa365247.aspx
        savepath_without_invalid_chars = re.sub(r'<|>|:|\"|\||\?|\*', '_',
                                                split_savepath[1])
        return split_savepath[0] + savepath_without_invalid_chars