def history_file(self, location=None):
if location:<EOL><INDENT>if os.path.exists(location):<EOL><INDENT>return location<EOL><DEDENT>else:<EOL><INDENT>logger.warn("<STR_LIT>",<EOL>location)<EOL><DEDENT><DEDENT>filenames = []<EOL>for base in ['<STR_LIT>', '<STR_LIT>', '<STR_LIT>']:<EOL><INDENT>filenames.append(base)<EOL>for extension in ['<STR_LIT>', '<STR_LIT>', '<STR_LIT>']:<EOL><INDENT>filenames.append('<STR_LIT:.>'.join([base, extension]))<EOL><DEDENT><DEDENT>history = self.filefind(filenames)<EOL>if history:<EOL><INDENT>return history<EOL><DEDENT>
Return history file location.