code: def is_ligature(archar):
      """Checks for Arabic  Ligatures like LamAlef.
      (LAM_ALEF, LAM_ALEF_HAMZA_ABOVE, LAM_ALEF_HAMZA_BELOW, LAM_ALEF_MADDA_ABOVE)
      @param archar: arabic unicode char
      @type archar: unicode
      @return:
      @rtype:Boolean
      """
      return archar in LIGUATURES
  
imports: import re
  from cltk.phonology.arb.utils.pyarabic import stack
label_desc: Use image node_id 8 for calling a global function with example usage: is_ligature(archar) and returns: unknown