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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 _validate_if_patch_supported(self, headers, uri):
 """Check if the PATCH Operation is allowed on the resource."""

        if not self._operation_allowed(headers, 'PATCH'):
                msg = ('PATCH Operation not supported on the resource '
                       '"%s"' % uri)
                raise exception.IloError(msg)