class_docstr: Base API generator class. We derive several subclasses to implement
  the different backends.
class_docstr_tok: ["Base","API","generator","class",".","We","derive","several","subclasses","to","implement","the","different","backends","."]
code: def add_function(self, des: FunctionDescription):
      if des.es2.group:
          if des.name.startswith("get"):
              assert len(des.es2.group) == 2  # vi and fv
              des.es2 = des.es2.group[0]  # f comes before 1
              self._add_function(des)
          else:
              self._add_function_group(des)
      else:
          self._add_function(des)
      self.lines.append("\n")
  
imports: from __future__ import annotations
  import os
  import sys
  import headerparser
  from annotations import parse_anotations
  from OpenGL import GL
label_desc: Use image node_id 4 for calling the ApiGenerator obj's underlying member method code with example usage: obj.add_function(des) without return types