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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 clone_data( self, source ):
 """Clone data from another Block. source Block instance to copy from. """

        klass = self.__class__
        assert isinstance( source, klass )

        for name in klass._fields:
            self._field_data[name] = getattr( source, name )