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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 xmlchars(text):
 Thus, this function can be used to remove illegal characters from ``text``. """

    invalid = list(range(0x9))
    invalid.extend([0xb, 0xc])
    invalid.extend(range(0xe, 0x20))
    return re.sub('|'.join('\\x%0.2X' % i for i in invalid), '', text)