Error when running example (pi.py)

[Ashish Kumar]

Traceback (most recent call last):
  File "pi.py", line 29, in <module>
    sc = SparkContext(appName="PythonPi")
  File
"/home/ashish/Downloads/spark-1.1.0-bin-hadoop2.4/python/pyspark/context.py",
line 104, in __init__
    SparkContext._ensure_initialized(self, gateway=gateway)
  File
"/home/ashish/Downloads/spark-1.1.0-bin-hadoop2.4/python/pyspark/context.py",
line 211, in _ensure_initialized
    SparkContext._gateway = gateway or launch_gateway()
  File
"/home/ashish/Downloads/spark-1.1.0-bin-hadoop2.4/python/pyspark/java_gateway.py",
line 48, in launch_gateway
    proc = Popen(command, stdout=PIPE, stdin=PIPE, preexec_fn=preexec_func)
  File "/usr/lib/python2.7/subprocess.py", line 710, in __init__
    errread, errwrite)
  File "/usr/lib/python2.7/subprocess.py", line 1327, in _execute_child
    raise child_exception
OSError: [Errno 13] Permission denied