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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 _create_main_config(cls, overrides=None):
 """See comment block at top of 'rezconfig' describing how the main config is assembled."""

        filepaths = []
        filepaths.append(get_module_root_config())
        filepath = os.getenv("REZ_CONFIG_FILE")
        if filepath:
            filepaths.extend(filepath.split(os.pathsep))

        filepath = os.path.expanduser("~/.rezconfig")
        filepaths.append(filepath)

        return Config(filepaths, overrides)