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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 unicode_http_header(value):
 r""" Convert an ASCII HTTP header string into a unicode string with the appropriate encoding applied. Expects headers to be RFC 2047 compliant. True True True """

    if six.PY3:  # pragma: no cover
        # email.header.decode_header expects strings, not bytes. Your input data may be in bytes.
        # Since these bytes are almost always ASCII, calling `.decode()` on it without specifying
        # a charset should work fine.
        if isinstance(value, six.binary_type):
            value = value.decode()
    return u''.join([six.text_type(s, e or 'iso-8859-1') if not isinstance(s, six.text_type) else s
        for s, e in decode_header(value)])