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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 command_clean(string, vargs):
 """ Remove characters that are not IPA valid from the given string, and print the remaining string. :param str string: the string to act upon :param dict vargs: the command line arguments """

    valid_chars, invalid_chars = remove_invalid_ipa_characters(
        unicode_string=string,
        return_invalid=True,
        single_char_parsing=vargs["single_char_parsing"]
    )
    print(u"".join(valid_chars))
    print_invalid_chars(invalid_chars, vargs)