class_docstr: Abstract class for manual scales
  
  Parameters
  ----------
  {superclass_parameters}
class_docstr_tok: ["Abstract","class","for","manual","scales","Parameters","--","--","--","--","--","{","superclass_parameters","}"]
code: def palette(self, value):
      max_n = len(self._values)
      if value > max_n:
          msg = (
              f"The palette of {self.__class__.__name__} can return a "
              f"maximum of {max_n} values. {value} were requested from it."
          )
          warn(msg, PlotnineWarning)
      return self._values
  
imports: from __future__ import annotations
  import typing
  from warnings import warn
  from .._utils.registry import alias
  from ..doctools import document
  from ..exceptions import PlotnineWarning
  from .scale_discrete import scale_discrete
label_desc: Use image node_id 2 for calling the _scale_manual obj's underlying member method code with example usage: obj.palette(value) and returns: self