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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 filename(self, value):
 """Deprecated, user `source'."""

        warnings.warn(
            "The 'filename' attribute will be removed in future versions.  "
            "Use 'source' instead.",
            DeprecationWarning, stacklevel=2
        )
        self.source = value