def cancel(self):
if not self.id:<EOL><INDENT>raise WorkflowError('<STR_LIT>')<EOL><DEDENT>if self.batch_values:<EOL><INDENT>self.workflow.batch_workflow_cancel(self.id)<EOL><DEDENT>else:<EOL><INDENT>self.workflow.cancel(self.id)<EOL><DEDENT>
Cancel a running workflow.

Args:
    None

Returns:
    None