Returns the value of Spark SQL configuration property for the given key.

        If the key is not set and defaultValue is set, return
        defaultValue. If the key is not set and defaultValue is not set, return
        the system default value.

        >>> sqlContext.getConf("spark.sql.shuffle.partitions")
        u'200'
        >>> sqlContext.getConf("spark.sql.shuffle.partitions", u"10")
        u'10'
        >>> sqlContext.setConf("spark.sql.shuffle.partitions", u"50")
        >>> sqlContext.getConf("spark.sql.shuffle.partitions", u"10")
        u'50'

def getConf(self, key, defaultValue=_NoValue):
        """Returns the value of Spark SQL configuration property for the given key.

        If the key is not set and defaultValue is set, return
        defaultValue. If the key is not set and defaultValue is not set, return
        the system default value.

        >>> sqlContext.getConf("spark.sql.shuffle.partitions")
        u'200'
        >>> sqlContext.getConf("spark.sql.shuffle.partitions", u"10")
        u'10'
        >>> sqlContext.setConf("spark.sql.shuffle.partitions", u"50")
        >>> sqlContext.getConf("spark.sql.shuffle.partitions", u"10")
        u'50'
        """
        return self.sparkSession.conf.get(key, defaultValue)