class_docstr: This is a generator convert from an input element to the partition key, a string.
class_docstr_tok: ["This","is","a","generator","convert","from","an","input","element","to","the","partition","key",",","a","string","."]
code: def __init__(self, j_partition_key_generator):
      self._j_partition_key_generator = j_partition_key_generator
  
imports: from typing import Dict, Union, List
  from pyflink.common import SerializationSchema, DeserializationSchema, AssignerWithPeriodicWatermarksWrapper
  from pyflink.datastream.functions import SourceFunction
  from pyflink.datastream.connectors import Sink
  from pyflink.java_gateway import get_gateway
label_desc: Use image node_id 1 to create a new PartitionKeyGenerator object from inherited base classes: object with example: obj = PartitionKeyGenerator(j_partition_key_generator)