class_docstr: Constants for defining target colors by input type
code: def validate(klass, val):
      if isinstance(val, klass):
          return
  
      try:
          klass(val)
      except ValueError:
          raise YellowbrickValueError(
              "unknown target color type '{}'".format(val)
          )
  
file_path: yellowbrick/yellowbrick/utils/target.py
imports: import numpy
  from enum import Enum
  from sklearn.utils.multiclass import type_of_target
  from yellowbrick.exceptions import YellowbrickValueError
label_desc: Use image node_id 1 for calling the TargetType obj's underlying member method code with example usage: obj.validate(klass, val) without return types