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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 copyto(self, src, where=None):
 """Emulates function `copyto` in NumPy. Parameters where: (N,) bool ndarray True if particle n in src must be copied. src: (N,) `ThetaParticles` object source for each n such that where[n] is True, copy particle n in src into self (at location n) """

        for k in self.containers:
            v = self.__dict__[k]
            if isinstance(v, np.ndarray):
                np.copyto(v, src.__dict__[k], where=where)
            else:
                v.copyto(src.__dict__[k], where=where)