def clear_breakpoint(self, filename, lineno):
        """Remove a single breakpoint"""
        clear_breakpoint(filename, lineno)
        self.breakpoints_saved.emit()
        editorstack = self.get_current_editorstack()
        if editorstack is not None:
            index = self.is_file_opened(filename)
            if index is not None:
                editorstack.data[index].editor.debugger.toogle_breakpoint(
                        lineno)
Remove a single breakpoint