Correct way to set Spark variables in jupyter notebook

I need to set a couple of variables in my Jupyter Notebook where I have a pre-existing sparkContext and sqlContext and I am doing it wrong. If I don't include an
sc.stop() , I get an error that I am trying to instantiate a second context. If I do include it, I get an error that I am trying to call methods on a stopped context.

Can someone tell me the correct way to set these variables?

Here is my code:

from pyspark import SparkConf, SparkContext
from pyspark.sql import HiveContext
from pyspark.sql import SQLContext
conf = (SparkConf()