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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 get_distance(self, i, j, jimage=None):
 """ Get distance between site i and j assuming periodic boundary conditions. If the index jimage of two sites atom j is not specified it selects the jimage nearest to the i atom and returns the distance and jimage indices in terms of lattice vector translations if the index jimage of atom j is specified it returns the distance between the i atom and the specified jimage atom. Args: i (int):
 Index of first site j (int):
 Index of second site jimage: Number of lattice translations in each lattice direction. Default is None for nearest image. Returns: distance """

        return self[i].distance(self[j], jimage)