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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 fingerprint(self):
 """A total graph fingerprint The result is invariant under permutation of the vertex indexes. The chance that two different (molecular) graphs yield the same fingerprint is small but not zero. (See unit tests.)"""

        if self.num_vertices == 0:
            return np.zeros(20, np.ubyte)
        else:
            return sum(self.vertex_fingerprints)