Using numpy

>>> numbers = [1,2,3,4,5]
>>> numpy.mean(numbers)
Traceback (most recent call last):
  File "", line 1, in 
NameError: name 'numpy' is not defined
>>> import numpy
>>> numbers = [1,2,3,4,5]
>>> numpy.mean(numbers)
3.0
>>> numpy.median(numbers)
3.0
>>> numpy.std(numbers)
1.4142135623730951