https://medium.com/@mmas/hadoop-streaming-practical-introduction-to-mapreduce-with-python-772bf08070c5

max_temperature_mapper.py

#!/usr/bin/env python

import sys


for line in sys.stdin:
    if not line.strip() or line.startswith('Wban'):
        continue
    _, k, v = line[:17].split(',', 2)
    try:
        v = int(v)
    except ValueError:
        continue
    print '%s\t%s' % (k, v)