replace content to all files by supply from input source text

sample.py

#!/usr/local/bin/python

import os
import sys
import errno
from datetime import datetime
from time import time

rootdir = os.getcwd()

commands = (

		'--setup',
		'--scan-dir',
		'--text-source',
		'--log'
	)

def parse_option(str):
	if '=' in str:
		return str.split('=')[1]

def run_setup():

	folders = ('runtime','sample','testing')
	for i in folders: 
		try:
			os.mkdir(rootdir+'/'+i)
			print 'Create directory {dir}'.format(dir=rootdir+'/'+i) 
		except OSError:
			print 'Directory already exists.'
			pass

def create_file():
	for d in os.listdir(rootdir):
		if os.path.isdir(d):
			f = open(os.path.join(os.getcwd(),d,'sample.cpp'),'w+')
			f.write('<replace_here>')
			f.close()

def usage():
	print 'Usage: python main.py'
	print 'example usage: python main.py --scan-dir=testing/dir --text-source=source-file.txt'
	print '--setup \t\t Run initial setup for simulation.\n'
	print '--scan-dir \t\t scan directory on current root. Set option --scan-dir=directory (unix style).\n'
	print '--text-source \t\t Replace all files with text inside source.\n'
	print '--log\t\t enable logging std output.'

if(len(sys.argv) <= 1 ): 
	usage()
else:

	options = sys.argv[1::]

	log = open(os.path.join(rootdir,'output.log'),'w+')

	source = parse_option(options[2])
	directory = parse_option(options[1])

	if os.path.isdir(source) == False or directory is None:

		real_dir = os.path.realpath(directory)
		if os.path.exists(source) == False:
			print 'file {file} source not found'.format(file=source)
		else:

			files = [x for x in os.listdir(real_dir) if os.path.isdir(x) == False]
			f = open(source,'r+')

			for file in files:
				content = ''.join([x for x in open(os.path.join(real_dir,file),'r+')])

				if '<replace_here>' in content:
					bak = open(os.path.join(real_dir,file+'.bak'),'w+')
					content = content.replace('<replace_here>',f.read())
					bak.write(content)

					print 'Replacing content {file}'.format(file=os.path.join(real_dir,file))
					log.write('Replacing content {file} \n'.format(file=os.path.join(real_dir,file)))
			
					original = file #dump to memory original name
 				
					print 'swap {backup} to original file {original_file}.'.format(backup=os.path.join(real_dir,original+'.bak'),original_file=os.path.join(real_dir,file))
					log.write('swap {backup} to original file {original_file}. \n'.format(backup=os.path.join(real_dir,original+'.bak'),original_file=os.path.join(real_dir,file)))
					
					os.remove(os.path.join(real_dir,original))
					os.rename(os.path.join(real_dir,original+'.bak'),os.path.join(real_dir,original))
					bak.close()
				else:

					print 'marker are not found inside this {file}'.format(file=os.path.join(real_dir,file))
					log.write('marker are not found inside this {file} \n'.format(file=os.path.join(real_dir,file)))