Mapper program : temperature_mapper.py
#!/usr/bin/env python 
import sys 
# input comes from standard input STDIN 
year=0; 
for data in sys.stdin: 
 data = data.strip() #remove leading and trailing whitespaces 
 yearData = data.split(',') #split the line into words and returns as a list 
 year = yearData[0]; 
 temperature_data=yearData[1:13] 
 print('%s %s' % (year, temperature_data)) #write the results to standard output STDOUT 
Reducer program: temperature_reducer.py 
#!/usr/bin/env python 
from operator import itemgetter 
import sys 
import ast 
# input comes from STDIN 
for line in sys.stdin: 
 line = line.strip() 
 new_year, new_temperature = line.split(' ',1) 
 list = ast.literal_eval(new_temperature) #Convert string to list 
 try: 
 new_year = int(new_year) 
 except ValueError: 
 continue 
 print("%s\t%s"%(new_year,max(list)))
 Reducer program : "reducer.py" 
#!/usr/bin/env python 
from operator import itemgetter 
import sys 
# using a dictionary to map words to their counts 
current_word = None 
current_count = 0 
word = None 
# input comes from STDIN 
for line in sys.stdin: 
 line = line.strip() 
 word, count = line.split(' ',1) 
 try: 
 count = int(count) 
 except ValueError: 
 continue 
 if current_word == word: 
 current_count += count 
 else: 
 if current_word: 
 print ('%s\t%s'%(current_word, current_count)) 
 current_count = count 
 current_word = word 
if current_word == word: 
 print ('%s\t%s'%(current_word,current_count))
 
 
 Mapper program
mapper.py
#!/usr/bin/env python 
import sys 
#Word Count Example 
# input comes from standard input STDIN 
for data in sys.stdin: 
 data = data.strip() #remove leading and trailing whitespaces 
 lines = data.split() #split the line into words and returns as a list 
 for word in lines: 
 #write the results to standard output STDOUT 
 print('%s %s' % (word, 1))