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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 Python encoding check."""


        encode = None

        m = RE_PY_ENCODE.match(content)
        if m:
            if m.group(1):
                encode = m.group(1).decode('ascii')
            elif m.group(2):
                encode = m.group(2).decode('ascii')
        if encode is None:
            encode = 'utf-8'
        return encode