<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def fit_transform(self, col):
 """Prepare the transformer and return processed data. Args: col(pandas.DataFrame):
 Data to transform. Returns: pandas.DataFrame """


        if self.anonymize:
            col = self.anonymize_column(col)

        self._fit(col)
        return self.transform(col)