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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 header_check(self, content):
 """Special HTML encoding check."""


        encode = None

        # Look for meta charset
        m = RE_HTML_ENCODE.search(content)
        if m:
            enc = m.group(1).decode('ascii')

            try:
                codecs.getencoder(enc)
                encode = enc
            except LookupError:
                pass
        else:
            encode = self._has_xml_encode(content)
        return encode