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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 __fix_field_date(self, item, attribute):
 """Fix possible errors in the field date"""


        field_date = str_to_datetime(item[attribute])

        try:
            _ = int(field_date.strftime("%z")[0:3])
        except ValueError:
            logger.warning("%s in commit %s has a wrong format", attribute, item['commit'])
            item[attribute] = field_date.replace(tzinfo=None).isoformat()