'Draws a rectangle.
:param box: A 4-tuple of integers whose order and function is currently
undocumented.
Hint: the tuple is passed into this format string:
.. code-block:: python
%d %d M %d %d 0 Vr'

def rectangle(self, box):

    self._fp_write(('%d    %d    M    %d    %d    0    Vr\n' % box))
