def placeholders(self, fill_missing=None):
        result = {
            K: self._format_placeholder(K, V)
            for K, V in self.values.items()
            if self._should_make_placeholder(K)
        }
        print('Making result!')
        if fill_missing is not None:
            for key in self.required:
                print('Checking out {}'.format(key))
                if self._should_make_placeholder(key) and not result.get(key):
                    result[key] = self._format_placeholder(key, fill_missing(key))
                    print('Added!', key, result[key])
        return result
Generate placeholder dict.
dataset/ETHPy150Open KeepSafe/ks-email-parser/email_parser/gui/gui.py/InlineFormReplacer.placeholders