'Set the hold state.  If hold is None (default), toggle the
hold state.  Else set the hold state to boolean value b.
e.g.::
hold()      # toggle hold
hold(True)  # hold is on
hold(False) # hold is off
All "hold" machinery is deprecated.'

@cbook.deprecated(u'2.0')
def hold(self, b=None):

    if (b is None):
        self._hold = (not self._hold)
    else:
        self._hold = b
