Shortcut for ``instrument.order("BUY", ...)`` and accepts all of its
        `optional parameters <#qtpylib.instrument.Instrument.order>`_

        :Parameters:
            quantity : int
                Order quantity

def buy(self, quantity, **kwargs):
        """ Shortcut for ``instrument.order("BUY", ...)`` and accepts all of its
        `optional parameters <#qtpylib.instrument.Instrument.order>`_

        :Parameters:
            quantity : int
                Order quantity
        """
        self.parent.order("BUY", self, quantity=quantity, **kwargs)