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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 activation_shell_code(self, shell=None):
 """Get shell code that should be run to activate this suite."""

        from rez.shells import create_shell
        from rez.rex import RexExecutor

        executor = RexExecutor(interpreter=create_shell(shell),
                               parent_variables=["PATH"],
                               shebang=False)
        executor.env.PATH.append(self.tools_path)
        return executor.get_output().strip()