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# Source code for langchain_community.graphs.kuzu_graph

    from typing import Any, Dict, List

    class KuzuGraph:
        """Kùzu wrapper for graph operations.

        *Security note*: Make sure that the database connection uses credentials
            that are narrowly-scoped to only include necessary permissions.
            Failure to do so may result in data corruption or loss, since the calling
            code may attempt commands that would result in deletion, mutation
            of data if appropriately prompted or reading sensitive data if such
            data is present in the database.
            The best way to guard against such negative outcomes is to (as appropriate)
            limit the permissions granted to the credentials used with this tool.

            See https://python.langchain.com/docs/security for more information.
        """

        def __init__(self, db: Any, database: str = "kuzu") -> None:
            try:
                import kuzu
            except ImportError:
                raise ImportError(
                    "Could not import Kùzu python package."
                    "Please install Kùzu with `pip install kuzu`."
                )
            self.db = db
            self.conn = kuzu.Connection(self.db)
            self.database = database
            self.refresh_schema()

        @property
        def get_schema(self) -> str:
            """Returns the schema of the Kùzu database"""
            return self.schema

        def query(self, query: str, params: dict = {}) -> List[Dict[str, Any]]:
            """Query Kùzu database"""
            result = self.conn.execute(query, params)
            column_names = result.get_column_names()
            return_list = []
            while result.has_next():
                row = result.get_next()
                return_list.append(dict(zip(column_names, row)))
            return return_list

        def refresh_schema(self) -> None:
            """Refreshes the Kùzu graph schema information"""
            node_properties = []
            node_table_names = self.conn._get_node_table_names()
            for table_name in node_table_names:
                current_table_schema = {"properties": [], "label": table_name}
                properties = self.conn._get_node_property_names(table_name)
                for property_name in properties:
                    property_type = properties[property_name]["type"]
                    list_type_flag = ""
                    if properties[property_name]["dimension"] > 0:
                        if "shape" in properties[property_name]:
                            for s in properties[property_name]["shape"]:
                                list_type_flag += "[%s]" % s
                        else:
                            for i in range(properties[property_name]["dimension"]):
                                list_type_flag += "[]"
                    property_type += list_type_flag
                    current_table_schema["properties"].append(
                        (property_name, property_type)
                    )
                node_properties.append(current_table_schema)

            relationships = []
            rel_tables = self.conn._get_rel_table_names()
            for table in rel_tables:
                relationships.append(
                    "(:%s)-[:%s]->(:%s)" % (table["src"], table["name"], table["dst"])
                )

            rel_properties = []
            for table in rel_tables:
                table_name = table["name"]
                current_table_schema = {"properties": [], "label": table_name}
                query_result = self.conn.execute(
                    f"CALL table_info('{table_name}') RETURN *;"
                )
                while query_result.has_next():
                    row = query_result.get_next()
                    prop_name = row[1]
                    prop_type = row[2]
                    current_table_schema["properties"].append((prop_name, prop_type))
                rel_properties.append(current_table_schema)

            self.schema = (
                f"Node properties: {node_properties}\n"
                f"Relationships properties: {rel_properties}\n"
                f"Relationships: {relationships}\n"
            )