From http://www.python-course.eu/lambda.php

lambda_map_reduce_filter.py

#lambda
#lambda parameter: expression
f = lambda x, y: x + y
f(15,1)
#=> 16
#using within a high order function
def my_function(x):
  return lambda arr: [x * each for each in arr]
fives = my_function(5)
print fives([1,2,3,4])
#=>[5,10,15,20]
#####################
#map()
#r= map(func, seq)
def my_function(x):
  return x**2
r = map(my_function,[1,2,3,4,5]) #map function to elemement of a sequence i.e list
#returns a new list
print r
#=> [1,4,9,16,25]

#Example 2:
def fahrenheit(T):
    return ((float(9)/5)*T + 32)
def celsius(T):
    return (float(5)/9)*(T-32)
temp = (36.5, 37, 37.5, 39)
F= map(fahrenheit, temp)
C= map(celsius, F)
#Another way of coding the above formulas is using lambda with map()
#A perfect use case for lambda, a throw away function that we won't need beyond this
Celsius = [39.2, 36.5, 37.3, 37.8]
Fahrenheit = map(lambda x: (float(9)/5)*x + 32, Celsius)
print Fahrenheit
[102.56, 97.700000000000003, 99.140000000000001, 100.03999999999999]
C = map(lambda x: (float(5)/9)*(x-32), Fahrenheit)
print C
[39.200000000000003, 36.5, 37.300000000000004, 37.799999999999997]