code: def add_pyspark_path():
      
  
      try:
          spark_home = os.environ['SPARK_HOME']
  
          sys.path.append(os.path.join(spark_home, 'python'))
          py4j_src_zip = glob(os.path.join(spark_home, 'python',
                                           'lib', 'py4j-*-src.zip'))
          if len(py4j_src_zip) == 0:
              raise ValueError('py4j source archive not found in %s'
                               % os.path.join(spark_home, 'python', 'lib'))
          else:
              py4j_src_zip = sorted(py4j_src_zip)[::-1]
              sys.path.append(py4j_src_zip[0])
      except KeyError:
          logging.error("""SPARK_HOME was not set. please set it. e.g.
            SPARK_HOME='/home/...' ./bin/pyspark [program]""")
          exit(-1)
      except ValueError as e:
          logging.error(str(e))
          exit(-1)
docs: Add PySpark to the library path based on the value of SPARK_HOME.