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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 _2(self):
 """python 2.x version of formatting body data"""

        boundary = self.boundary
        buf = StringIO()
        for (key, value) in self.form_fields:
            buf.write('--%s\r\n' % boundary)
            buf.write('Content-Disposition: form-data; name="%s"' % key)
            buf.write('\r\n\r\n%s\r\n' % value)
        for (key, filename, mimetype, filepath) in self.files:
            if os.path.isfile(filepath):
                buf.write('--{boundary}\r\n'
                          'Content-Disposition: form-data; name="{key}"; '
                          'filename="{filename}"\r\n'
                          'Content-Type: {content_type}\r\n\r\n'.format(
                              boundary=boundary,
                              key=key,
                              filename=filename,
                              content_type=mimetype))
                with open(filepath, "rb") as f:
                    shutil.copyfileobj(f, buf)
                buf.write('\r\n')
        buf.write('--' + boundary + '--\r\n\r\n')
        buf = buf.getvalue()
        self.form_data = buf