code: def find_tool(name, additional_paths = [], path_last = False):
      
      assert isinstance(name, basestring)
      assert is_iterable_typed(additional_paths, basestring)
      assert isinstance(path_last, (int, bool))
  
      programs = path.programs_path()
      match = path.glob(programs, [name, name + '.exe'])
      additional_match = path.glob(additional_paths, [name, name + '.exe'])
  
      result = []
      if path_last:
          result = additional_match
          if not result and match:
              result = match
  
      else:
          if match:
              result = match
  
          elif additional_match:
              result = additional_match
  
      if result:
          return path.native(result[0])
      else:
          return ''
docs: Attempts to find tool (binary) named 'name' in PATH and in
          'additional-paths'.  If found in path, returns 'name'.  If
          found in additional paths, returns full name.  If the tool
          is found in several directories, returns the first path found.
          Otherwise, returns the empty string.  If 'path_last' is specified,
          path is checked after 'additional_paths'.