import csv

#filename = 'data.csv'
#lookfor = 'Paul'

filename = '/var/junk/kinne/weather/Terre_Haute_airport_93823-03868.csv'

record_h = None

with open(filename, 'r') as f:
    dr = csv.DictReader(f)
    for row in dr:
        #if row['Name'] == lookfor:
        #    print(row)
        if row['TMAX'] != 'M':
           if record_h == None or row['TMAX'] > record_h:
               record_h = row['TMAX']
               print(row)
print(record_h)