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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(self):
 """ Validate the input data. """

        if self.data_format is FormatType.PYTHON:
            self.data = self.raw_data
        elif self.data_format is FormatType.JSON:
            self._validate_json()
        elif self.data_format is FormatType.YAML:
            self._validate_yaml()