class_docstr: Completer which can be used for autocompletion according to variables in
  the grammar. Each variable can have a different autocompleter.
  
  :param compiled_grammar: `GrammarCompleter` instance.
  :param completers: `dict` mapping variable names of the grammar to the
                     `Completer` instances to be used for each variable.
code: def get_completions(self, document, complete_event):
      m = self.compiled_grammar.match_prefix(
          document.text_before_cursor
      )
  
      if m:
          completions = self._remove_duplicates(
              self._get_completions_for_match(m, complete_event)
          )
  
          for c in completions:
              yield c
  
file_path: catboost/contrib/python/prompt-toolkit/py2/prompt_toolkit/contrib/regular_languages/completion.py
imports: from __future__ import unicode_literals
  from prompt_toolkit.completion import Completer, Completion
  from prompt_toolkit.document import Document
  from .compiler import _CompiledGrammar
label_desc: Use image node_id 2 for calling the GrammarCompleter obj's underlying member method code with example usage: obj.get_completions(document, complete_event) without return types