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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 drop_database(self):
 """ Drop postgres database. """

        self.print_message("Dropping database '%s'" % self.databases['destination']['name'])
        self.export_pgpassword('destination')
        args = [
            "dropdb",
            "--if-exists",
            self.databases['destination']['name'],
        ]
        args.extend(self.databases['destination']['args'])
        subprocess.check_call(args)