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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_at(self, n, src, m):
 """Copy to at a given location. Parameters n: int index where to copy src: `ThetaParticles` object source m: int index of the element to be copied Note ---- Basically, does self[n] <- src[m] """

        for k in self.containers:
            self.__dict__[k][n] = src.__dict__[k][m]