code: def get_file_extension(file_path):
      
      _ext = os.path.splitext(file_path)[-1]
      if _ext:
          return _ext[1:] if _ext.startswith('.') else _ext
  
      return ""
docs: >>> get_file_extension("/a/b/c")
      ''
      >>> get_file_extension("/a/b.txt")
      'txt'
      >>> get_file_extension("/a/b/c.tar.xz")
      'xz'