python.py 文件源码

def __repr__(self):
        if isinstance(self.expected, complex):
            return str(self.expected)

        # Infinities aren't compared using tolerances, so don't show a
        # tolerance.
        if math.isinf(self.expected):
            return str(self.expected)

        # If a sensible tolerance can't be calculated, self.tolerance will
        # raise a ValueError.  In this case, display '???'.
        try:
            vetted_tolerance = '{:.1e}'.format(self.tolerance)
        except ValueError:
            vetted_tolerance = '???'

        if sys.version_info[0] == 2:
            return '{0} +- {1}'.format(self.expected, vetted_tolerance)
        else:
            return u'{0} \u00b1 {1}'.format(self.expected, vetted_tolerance)