snake2lowerCamel.py

#! /usr/bin/env python3

from sys import stderr, argv

if len(argv) <= 1:
    stderr.write("No file names are specified.\n")
    exit(1)


prev = ''
s = ''

for l in open(argv[1], mode='r'):
    for c in l:
        if prev == '_':
            if c == '_':
                s += '_'
                c = ''
            if c.islower():
                c = c.capitalize()
                prev = ''

        s += prev
        prev = c

print(s + prev)