@check_for(Definition)<EOL><INDENT>def check_ends_with_period(self, definition, docstring):<DEDENT>
if docstring:<EOL><INDENT>summary_line = ast.literal_eval(docstring).strip().split('<STR_LIT:\n>')[<NUM_LIT:0>]<EOL>if not summary_line.endswith('<STR_LIT:.>'):<EOL><INDENT>return violations.D400(summary_line[-<NUM_LIT:1>])<EOL><DEDENT><DEDENT>
D400: First line should end with a period.

        The [first line of a] docstring is a phrase ending in a period.