old_contents: from . import parser
  
  
  class FlagSet(list):
  
      def __getattr__(self, name):
  
          return 2 ** self.index(name)
  
  
  class AttrDict (dict):
  
      def __getattr__(self, name):
  
          try:
  
              return self[name]
  
          except KeyError:
  
              raise AttributeError(name)
  
  
  CO = FlagSet([  # code flags
      'OPTIMIZED'  # PyFrame should ignore `f_locals` in favor of fast slots
    , 'NEWLOCALS'  # PyFrame should create a new dict for `f_locals`
    , 'VARARGS'    # code object is a function with *varargs
    , 'VARKWARGS'  # code object is a function with *varkwargs
    , 'NESTED'     # code object uses non-local variables
    , 'GENERATOR'  # code object yields values
    , 'NOFREE'     # code object is NOT a closure neither it produces one
  ])
  
  
  ERR = AttrDict(  # error descriptions
  
      DEFAULT = 'invalid syntax'
  
    ### SYNTAX
  
      # Attempted to store an imported module in a non-variable (e.g. object attribute.)
    , NONCONST_IMPORT = 'use `__import__` instead'
      # Attempted to pass a kwarg with an invalid name.
    , NONCONST_KEYWORD = 'keyword argument names should be constant'
      # Attempted to get an attribute by non-constant name.
    , NONCONST_ATTR = 'can\'t access attributes with non-constant names'
      # Attempted to assign a value to something but a name.
    , NONCONST_VARNAME = 'can\'t assign to non-constant names'
  
      # Two or more *varargs definitions.
    , MULTIPLE_VARARGS = 'multiple *varargs are not allowed'
      # Same as above, but for **varkwargs.
    , MULTIPLE_VARKWARGS = 'multiple **varkwargs are not allowed'
      # *varargs or **varkwargs have been assigned a default value in function definition.
    , VARARG_DEFAULT = 'neither *varargs nor **varkwargs can have default values'
      # **varkwargs is not the last argument in function definition.
    , ARG_AFTER_VARKWARGS = '**varkwargs must be the last argument'
  
    ### UNDEFINED BEHAVIOR
  
      # Attempted to assign a value to a non-local variable.
    , FREEVAR_ASSIGNMENT = 'can\'t assign to free variables'
  
    ### CPYTHON LIMITATIONS
  
      # More than 255 arguments in a function definition.
    , TOO_MANY_ARGS = 'CPython can\'t into 256+ arguments'
      # More than 255 items before a *starred expression in iterable unpacking.
    , TOO_MANY_ITEMS_BEFORE_STAR = 'too many items before a *starred expression'
      # An argument between one with a default value and *varargs lacks such a value.
    , NO_DEFAULT = 'one of the arguments lacks the required default value'
  
  )
  
  
  AT = FlagSet([  # assignment types
      'IMPORT'
    , 'UNPACK'
    , 'ATTR'
    , 'ITEM'
    , 'NAME'
  ])
  
new_contents: class FlagSet(list):
  
      def __getattr__(self, name):
  
          return 2 ** self.index(name)
  
  
  class AttrDict (dict):
  
      def __getattr__(self, name):
  
          try:
  
              return self[name]
  
          except KeyError:
  
              raise AttributeError(name)
  
  
  CO = FlagSet([  # code flags
      'OPTIMIZED'  # PyFrame should ignore `f_locals` in favor of fast slots
    , 'NEWLOCALS'  # PyFrame should create a new dict for `f_locals`
    , 'VARARGS'    # code object is a function with *varargs
    , 'VARKWARGS'  # code object is a function with *varkwargs
    , 'NESTED'     # code object uses non-local variables
    , 'GENERATOR'  # code object yields values
    , 'NOFREE'     # code object is NOT a closure neither it produces one
  ])
  
  
  ERR = AttrDict(  # error descriptions
  
      DEFAULT = 'invalid syntax'
  
    ### SYNTAX
  
      # Attempted to store an imported module in a non-variable (e.g. object attribute.)
    , NONCONST_IMPORT = 'use `__import__` instead'
      # Attempted to pass a kwarg with an invalid name.
    , NONCONST_KEYWORD = 'keyword argument names should be constant'
      # Attempted to get an attribute by non-constant name.
    , NONCONST_ATTR = 'can\'t access attributes with non-constant names'
      # Attempted to assign a value to something but a name.
    , NONCONST_VARNAME = 'can\'t assign to non-constant names'
  
      # Two or more *varargs definitions.
    , MULTIPLE_VARARGS = 'multiple *varargs are not allowed'
      # Same as above, but for **varkwargs.
    , MULTIPLE_VARKWARGS = 'multiple **varkwargs are not allowed'
      # *varargs or **varkwargs have been assigned a default value in function definition.
    , VARARG_DEFAULT = 'neither *varargs nor **varkwargs can have default values'
      # **varkwargs is not the last argument in function definition.
    , ARG_AFTER_VARKWARGS = '**varkwargs must be the last argument'
  
    ### UNDEFINED BEHAVIOR
  
      # Attempted to assign a value to a non-local variable.
    , FREEVAR_ASSIGNMENT = 'can\'t assign to free variables'
  
    ### CPYTHON LIMITATIONS
  
      # More than 255 arguments in a function definition.
    , TOO_MANY_ARGS = 'CPython can\'t into 256+ arguments'
      # More than 255 items before a *starred expression in iterable unpacking.
    , TOO_MANY_ITEMS_BEFORE_STAR = 'too many items before a *starred expression'
      # An argument between one with a default value and *varargs lacks such a value.
    , NO_DEFAULT = 'one of the arguments lacks the required default value'
  
  )
  
  
  AT = FlagSet([  # assignment types
      'IMPORT'
    , 'UNPACK'
    , 'ATTR'
    , 'ITEM'
    , 'NAME'
  ])
  
subject: Remove unused import from const.