def set_std(self, std):
if not hasattr(self, '<STR_LIT>'):<EOL><INDENT>IMap.__init__(self)<EOL><DEDENT>self._std = std.lower()<EOL>self._set_transmaps()<EOL>if self._lower_chars:<EOL><INDENT>self._lower_trans = str.maketrans(self._upper_chars, self._lower_chars)<EOL><DEDENT>if self._upper_chars:<EOL><INDENT>self._upper_trans = str.maketrans(self._lower_chars, self._upper_chars)<EOL><DEDENT>
Set the standard we'll be using (isupport CASEMAPPING).