new_contents: import sys, tokenizer, parser, ast, codegen, os
  
  def llir(fn):
  	src = open(fn).read()
  	tokens = tokenizer.indented(tokenizer.tokenize(src))
  	mod = ast.Module.parse(parser.Buffer(tokens))
  	return codegen.source(mod)
  
  def compile(fn):
  	
  	llfn = fn + '.ll'
  	with open(llfn, 'w') as f:
  		f.write(llir(fn))
  	
  	cmd = 'llvmc', '-o', fn.rsplit('.', 1)[0], llfn
  	proc = os.popen(' '.join(cmd))
  	proc.read()
  	os.unlink(llfn)
  
  if __name__ == '__main__':
  	compile(sys.argv[1])
  
subject: Add a compiler driver.