code: def _is_diphthong(char_1: str, char_2: str) -> bool:
      """Checks if two sequential characters compose a diphthong"""
      return char_1 + char_2 in LATIN["diphthongs"]
  
file_path: cltk/src/cltk/phonology/lat/syllabifier.py
imports: import re
  from typing import List
label_desc: Use image node_id 3 for calling a global function with example usage: _is_diphthong(char_1, char_2) and returns: unknown