code: def appellf4(ctx, a, b, c1, c2, x, y, **kwargs):
      # TODO: continuation
      return ctx.hyper2d(
          {"m+n": [a, b]}, {"m": [c1], "n": [c2]}, x, y, **kwargs
      )
  
imports: from ..libmp.backend import xrange
  from .functions import defun, defun_wrapped
label_desc: Use image node_id 27 for calling a global function with example usage: appellf4(ctx, a, b, c1, c2, x, y) and returns: ctx