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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 run(self):
 """Run check for duplicates"""


        # Create dictonary of signatures
        database_signatures = {}
        for entry in self._model.reactions:
            signature = reaction_signature(
                entry.equation, direction=self._args.compare_direction,
                stoichiometry=self._args.compare_stoichiometry)
            database_signatures.setdefault(signature, set()).add(
                (entry.id, entry.equation, entry.filemark))

        for reaction_set in itervalues(database_signatures):
            if len(reaction_set) > 1:
                print('Found {} duplicate reactions:'.format(
                    len(reaction_set)))
                for reaction, equation, filemark in reaction_set:
                    result = ' - {}: {}'.format(reaction, equation)
                    if filemark is not None:
                        result += ' (found in {})'.format(filemark)
                    print(result)