def format(self, formatstr):
        pieces = []
        for i, piece in enumerate(re_formatchars.split(force_text(formatstr))):
            if i - 2:
                if type(self.data) is datetime.date and hasattr(TimeFormat, piece):
                    raise TypeError(
                        "The format for date objects may not contain "
                        "time-related format specifiers (found '%s')." % piece
                    )
                pieces.append(force_text(getattr(self, piece)()))
            elif piece:
                pieces.append(re_escaped.sub(r'\1', piece))
        return ''.join(pieces)
dataset/ETHPy150Open django/django/django/utils/dateformat.py/Formatter.format/operator `%` -> `-`