code: def add(self, abspath_or_winfile, enable_verbose=True):
          
          if isinstance(abspath_or_winfile, str): # abspath
              if abspath_or_winfile in self.files:
                  if enable_verbose:
                      print("'%s' already in this collections" % 
                            abspath_or_winfile)
              else:
                  self.files.setdefault(abspath_or_winfile, WinFile(abspath_or_winfile))
          elif isinstance(abspath_or_winfile, WinFile): # WinFile
              if abspath_or_winfile.abspath in self.files:
                  if enable_verbose:
                      print("'%s' already in this collections" % 
                            abspath_or_winfile)
              else:
                  self.files.setdefault(abspath_or_winfile.abspath, abspath_or_winfile)
          else:
              raise TypeError
docs: Add absolute path or WinFile to FileCollection.