Skew the object.

            >>> obj.skewBy(11)
            >>> obj.skewBy((25, 10), origin=(500, 500))

        **value** must be rone of the following:

        * single :ref:`type-int-float` indicating the
          value to skew the x direction by.
        * iterable cointaining type :ref:`type-int-float`
          defining the values to skew the x and y directions by.

        **origin** defines the point at with the skew should
        originate. It must be a :ref:`type-coordinate` or
        ``None``. The default is ``(0, 0)``.

def skewBy(self, value, origin=None):
        """
        Skew the object.

            >>> obj.skewBy(11)
            >>> obj.skewBy((25, 10), origin=(500, 500))

        **value** must be rone of the following:

        * single :ref:`type-int-float` indicating the
          value to skew the x direction by.
        * iterable cointaining type :ref:`type-int-float`
          defining the values to skew the x and y directions by.

        **origin** defines the point at with the skew should
        originate. It must be a :ref:`type-coordinate` or
        ``None``. The default is ``(0, 0)``.
        """
        value = normalizers.normalizeTransformationSkewAngle(value)
        if origin is None:
            origin = (0, 0)
        origin = normalizers.normalizeCoordinateTuple(origin)
        self._skewBy(value, origin=origin)