def validate_data_columns(self, data_columns, min_itemsize):
if not len(self.non_index_axes):<EOL><INDENT>return []<EOL><DEDENT>axis, axis_labels = self.non_index_axes[<NUM_LIT:0>]<EOL>info = self.info.get(axis, dict())<EOL>if info.get('<STR_LIT:type>') == '<STR_LIT>' and data_columns:<EOL><INDENT>raise ValueError("<STR_LIT>"<EOL>"<STR_LIT>".format(axis, data_columns))<EOL><DEDENT>if data_columns is True:<EOL><INDENT>data_columns = list(axis_labels)<EOL><DEDENT>elif data_columns is None:<EOL><INDENT>data_columns = []<EOL><DEDENT>if isinstance(min_itemsize, dict):<EOL><INDENT>existing_data_columns = set(data_columns)<EOL>data_columns.extend([<EOL>k for k in min_itemsize.keys()<EOL>if k != '<STR_LIT>' and k not in existing_data_columns<EOL>])<EOL><DEDENT>return [c for c in data_columns if c in axis_labels]<EOL>
take the input data_columns and min_itemize and create a data
        columns spec