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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 relabel_atoms(self, start=1):
 """Relabels all Atoms in numerical order, offset by the start parameter. Parameters start : int, optional Defines an offset for the labelling. """

        counter = start
        for atom in self.get_atoms(ligands=True):
            atom.id = counter
            counter += 1
        return