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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 xyz(self, arrnx3):
 """Set the positions of the particles in the Compound, excluding the Ports. This function does not set the position of the ports. Parameters arrnx3 : np.ndarray, shape=(n,3), dtype=float The new particle positions """

        if not self.children:
            if not arrnx3.shape[0] == 1:
                raise ValueError(
                    'Trying to set position of {} with more than one'
                    'coordinate: {}'.format(
                        self, arrnx3))
            self.pos = np.squeeze(arrnx3)
        else:
            for atom, coords in zip(
                self._particles(
                    include_ports=False), arrnx3):
                atom.pos = coords