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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 readfp(self, fp, filename=None):
 """Deprecated, use read_file instead."""

        warnings.warn(
            "This method will be removed in future versions.  "
            "Use 'parser.read_file()' instead.",
            DeprecationWarning, stacklevel=2
        )
        self.read_file(fp, source=filename)