def assertAlmostEqual(self, first, second, places=7, msg=None):
        """
        Fail if the two objects are unequal as determined by their
        difference rounded to the given number of decimal places
        (default 7) and comparing to zero.

        @note: decimal places (from zero) is usually not the same
               as significant digits (measured from the most
               significant digit).

        @note: included for compatibility with PyUnit test cases
        """
        if round(second-first, places) != 0:
            raise self.failureException(msg or '%r != %r within %r places'
                                        % (first, second, places))
        return first

        Fail if the two objects are unequal as determined by their
        difference rounded to the given number of decimal places
        (default 7) and comparing to zero.

        @note: decimal places (from zero) is usually not the same
               as significant digits (measured from the most
               significant digit).

        @note: included for compatibility with PyUnit test cases
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/trial/_synctest.py