fixed PEP-008 violation

Author: giwa

python/pyspark/streaming/context.py

@@ -19,10 +19,6 @@
 from signal import signal, SIGTERM, SIGINT
 from tempfile import NamedTemporaryFile
 
-
-from pyspark.conf import SparkConf
-from pyspark.files import SparkFiles
-from pyspark.java_gateway import launch_gateway
 from pyspark.serializers import PickleSerializer, BatchedSerializer, UTF8Deserializer
 from pyspark.context import SparkContext
 from pyspark.streaming.dstream import DStream