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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_field_mapping_action(self):
 """Create action for showing field mapping dialog."""

        icon = resources_path('img', 'icons', 'show-mapping-tool.svg')
        self.action_field_mapping = QAction(
            QIcon(icon),
            self.tr('InaSAFE Field Mapping Tool'),
            self.iface.mainWindow())
        self.action_field_mapping.setStatusTip(self.tr(
            'Assign field mapping to layer.'))
        self.action_field_mapping.setWhatsThis(self.tr(
            'Use this tool to assign field mapping in layer.'))
        self.action_field_mapping.setEnabled(False)
        self.action_field_mapping.triggered.connect(self.show_field_mapping)
        self.add_action(
            self.action_field_mapping, add_to_toolbar=self.full_toolbar)