code: def startswith(string, prefix):
      
      return string.startswith(prefix) and safe_split_index(string, len(prefix)) == len(prefix)
docs: Like str.startswith, but also checks that the string starts with the given prefixes sequence of graphemes.
  
      str.startswith may return true for a prefix that is not visually represented as a prefix if a grapheme cluster
      is continued after the prefix ends.
  
      >>> grapheme.startswith("✊🏾", "✊")
      False
      >>> "✊🏾".startswith("✊")
      True