     >>> from fractions import Fraction
        >>> start = Fraction(1, 2)  # Start at 1/2
        >>> stop = Fraction(5, 2)  # End at 5/2
        >>> step = Fraction(1, 2)  # Count by 1/2
        >>> list(numeric_range(start, stop, step))
        [Fraction(1, 2), Fraction(1, 1), Fraction(3, 2), Fraction(2, 1)]

    If *step* is zero, ``ValueError`` is raised. Negative steps are supported:

        >>> list(numeric_range(3, -1, -1.0))
        [3.0, 2.0, 1.0, 0.0]

    Be aware of the limitations of floating point numbers; the representation
    of the yielded numbers may be surprising.

    ``datetime.datetime`` objects can be used for *start* and *stop*, if *step*
    is a ``datetime.timedelta`` object:

        >>> import datetime
        >>> start = datetime.datetime(2019, 1, 1)
        >>> stop = datetime.datetime(2019, 1, 3)
        >>> step = datetime.timedelta(days=1)
        >>> items = iter(numeric_range(start, stop, step))
        >>> next(items)
        datetime.datetime(2019, 1, 1, 0, 0)
        >>> next(items)
        datetime.datetime(2019, 1, 2, 0, 0)

    r