old_contents: #!/usr/bin/env python
  """
  :Author Patrik Valkovic
  :Created 23.06.2017 16:39
  :Licence GNUv3
  Part of grammpy-transforms
  
  """
  
  from grammpy import Grammar
  from .NongeneratingSymbolsRemove import remove_nongenerating_symbols
  
  
  class ContextFree():
      @staticmethod
      def remove_nongenerating_symbols(grammar: Grammar, transform_grammar=False):
          return remove_nongenerating_symbols(grammar, transform_grammar)
  
      @staticmethod
      def is_grammar_generating(grammar: Grammar):
          g = ContextFree.remove_nongenerating_symbols(grammar)
          return g.start_get() in g.nonterms()
  
new_contents: #!/usr/bin/env python
  """
  :Author Patrik Valkovic
  :Created 23.06.2017 16:39
  :Licence GNUv3
  Part of grammpy-transforms
  
  """
  
  from grammpy import Grammar
  from .NongeneratingSymbolsRemove import remove_nongenerating_symbols
  
  
  class ContextFree:
      @staticmethod
      def remove_nongenerating_symbols(grammar: Grammar, transform_grammar=False):
          return remove_nongenerating_symbols(grammar, transform_grammar)
  
      @staticmethod
      def is_grammar_generating(grammar: Grammar, tranform_gramar=False, perform_remove=True):
          g = grammar
          if perform_remove:
              g = ContextFree.remove_nongenerating_symbols(grammar, transform_grammar=tranform_gramar)
          return g.start_get() in g.nonterms()
  
subject: Add additional parameters into CotextFree.is_grammar_generating method