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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def move_position(self, dx, dy, speed=None):
        ''' Move chuck relative to actual position in um'''
        if speed:
            self._intf.write('MoveChuckPosition %1.1f %1.1f R Y %d' % (dx, dy, speed))
        else:
            self._intf.write('MoveChuckPosition %1.1f %1.1f R Y' % (dx, dy))