code: def TeXLaTeXStrFunction(target = None, source= None, env=None):
      
      if env.GetOption("no_exec"):
  
          # find these paths for use in is_LaTeX to search for included files
          basedir = os.path.split(str(source[0]))[0]
          abspath = os.path.abspath(basedir)
  
          if is_LaTeX(source,env,abspath):
              result = env.subst('$LATEXCOM',0,target,source)+" ..."
          else:
              result = env.subst("$TEXCOM",0,target,source)+" ..."
      else:
          result = ''
      return result
docs: A strfunction for TeX and LaTeX that scans the source file to
      decide the "flavor" of the source and then returns the appropriate
      command string.