gistfile1.py

import sys
def bad_line(line, index):
    if line[index] != 'U':
        return True

def process_file(f, index):
    index = int(index)
    bad_records = []
    for i,line in enumerate(f):
        if line.strip():
            if bad_line(line, index):
                bad_records.append((i,line))
    return bad_records

def main():
    filename = sys.argv[1]
    index = sys.argv[2]
    
    f = open(filename)
    
    bad = process_file(f, index)
    print "BAD RECORDS"
    print ','.join([str(line[0]) for line in bad])

if __name__=="__main__":
    main()