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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 _on_remove_library(self, *event):
 """Callback method handling the removal of an existing library """

        self.view['library_tree_view'].grab_focus()
        if react_to_event(self.view, self.view['library_tree_view'], event):
            path = self.view["library_tree_view"].get_cursor()[0]
            if path is not None:
                library_name = self.library_list_store[int(path[0])][0]
                library_config = self.core_config_model.get_current_config_value("LIBRARY_PATHS", use_preliminary=True,
                                                                                 default={})
                del library_config[library_name]
                self.core_config_model.set_preliminary_config_value("LIBRARY_PATHS", library_config)
                if len(self.library_list_store) > 0:
                    self.view['library_tree_view'].set_cursor(min(path[0], len(self.library_list_store) - 1))
            return True