<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def show_field_mapping(self):
 """Show InaSAFE Field Mapping."""

        from safe.gui.tools.field_mapping_dialog import FieldMappingDialog
        dialog = FieldMappingDialog(
            parent=self.iface.mainWindow(),
            iface=self.iface,)
        if dialog.exec_():  # modal
            LOGGER.debug('Show field mapping accepted')
            self.dock_widget.layer_changed(self.iface.activeLayer())
        else:
            LOGGER.debug('Show field mapping not accepted')