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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 encode_request(self, fields, files):
 """ Encode fields and files for posting to an HTTP server. :param fields: The fields to send as a list of (fieldname, value) tuples. :param files: The files to send as a list of (fieldname, filename, file_bytes) tuple. """

        # Adapted from packaging, which in turn was adapted from
        # http://code.activestate.com/recipes/146306

        parts = []
        boundary = self.boundary
        for k, values in fields:
            if not isinstance(values, (list, tuple)):
                values = [values]

            for v in values:
                parts.extend((
                    b'--' + boundary,
                    ('Content-Disposition: form-data; name="%s"' %
                     k).encode('utf-8'),
                    b'',
                    v.encode('utf-8')))
        for key, filename, value in files:
            parts.extend((
                b'--' + boundary,
                ('Content-Disposition: form-data; name="%s"; filename="%s"' %
                 (key, filename)).encode('utf-8'),
                b'',
                value))

        parts.extend((b'--' + boundary + b'--', b''))

        body = b'\r\n'.join(parts)
        ct = b'multipart/form-data; boundary=' + boundary
        headers = {
            'Content-type': ct,
            'Content-length': str(len(body))
        }
        return Request(self.url, body, headers)