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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_chars(string, vargs):
 """ Print a list of all IPA characters in the given string. It will print the Unicode representation, the full IPA name, and the Unicode "U+"-prefixed hexadecimal codepoint representation of each IPA character. :param str string: the string to act upon :param dict vargs: the command line arguments """

    try:
        ipa_string = IPAString(
            unicode_string=string,
            ignore=vargs["ignore"],
            single_char_parsing=vargs["single_char_parsing"]
        )
        for c in ipa_string:
            print(u"'%s'\t%s (%s)" % (c.unicode_repr, c.name, unicode_to_hex(c.unicode_repr)))
    except ValueError as exc:
        print_error(str(exc))