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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 scan_for_field(self, field_key):
        '''
        Scan for a field in the container and its enclosed fields

        :param field_key: name of field to look for
        :return: field with name that matches field_key, None if not found
        '''
        if field_key == self.get_name():
            return self
        if field_key in self._fields_dict:
            return self._fields_dict[field_key]
        for field in self._fields:
            if isinstance(field, Container):
                resolved = field.scan_for_field(field_key)
                if resolved:
                    return resolved
        return None