def by_column_definition_id(self,column_definition_id: str) -> ColumnDefinitionItemRequestBuilder:
        """
        Provides operations to manage the externalColumns property of the microsoft.graph.site entity.
        param column_definition_id: The unique identifier of columnDefinition
        Returns: ColumnDefinitionItemRequestBuilder
        """
        if column_definition_id is None:
            raise TypeError("column_definition_id cannot be null.")
        from .item.column_definition_item_request_builder import ColumnDefinitionItemRequestBuilder

        url_tpl_params = get_path_parameters(self.path_parameters)
        url_tpl_params["columnDefinition%2Did"] = column_definition_id
        return ColumnDefinitionItemRequestBuilder(self.request_adapter, url_tpl_params)

        Provides operations to manage the externalColumns property of the microsoft.graph.site entity.
        param column_definition_id: The unique identifier of columnDefinition
        Returns: ColumnDefinitionItemRequestBuilder
        
msgraph/generated/groups/item/sites/item/external_columns/external_columns_request_builder.py