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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 _get_library_os_path_from_library_dict_tree(self, library_path, library_name):
 """Hand verified library os path from libraries dictionary tree."""

        if library_path is None or library_name is None:
            return None
        path_list = library_path.split(os.sep)
        target_lib_dict = self.libraries
        # go down the path to the correct library
        for path_element in path_list:
            if path_element not in target_lib_dict:  # Library cannot be found
                target_lib_dict = None
                break
            target_lib_dict = target_lib_dict[path_element]
        return None if target_lib_dict is None or library_name not in target_lib_dict else target_lib_dict[library_name]