def isOnAxis(self):
        """
        Returns statements about this location:
        
            *   False if the location is not on-axis
            *   The name of the axis if it is on-axis
            *   None if the Location is at the origin

        Note: this is only valid for an unbiased location.
        ::

            >>> l = Location(pop=1)
            >>> l.isOnAxis()
            'pop'
            >>> l = Location(pop=1, snap=1)
            >>> l.isOnAxis()
            False
            >>> l = Location()
            >>> l.isOnAxis() is None
            True
        """     
        new = self.__class__()
        new.update(self)
        s = new.strip()
        dims = list(s.keys())
        if len(dims)> 1:
            return False
        elif len(dims)==1:
            return dims[0]
        return None