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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 main_module(self):
 """Return the main module to which the receiver belongs."""

        if self.i_module.keyword == "submodule":
            return self.i_module.i_ctx.get_module(
                self.i_module.i_including_modulename)
        return self.i_module