code: def __init__(self):
      def filter(val):
          if val == "":
              return val
          for v in val.split(";"):
              s = v.split("->")
              if len(s) != 2:
                  raise ValueError("Malformed context map: %s" % (v,))
              if (
                  s[0] == "cpu"
                  or s[0].startswith("cuda")
                  or s[0].startswith("opencl")
              ):
                  raise ValueError(
                      "Cannot use %s as context name" % (s[0],)
                  )
          return val
  
      ConfigParam.__init__(self, "", filter, False)
  
imports: from __future__ import absolute_import, print_function, division
  import errno
  import os
  import sys
  import logging
  import numpy
  import platform
  import textwrap
  import re
  import socket
  import struct
  import warnings
  from six import string_types
  import theano
  from theano.configparser import AddConfigVar, BoolParam, ConfigParam, EnumStr, FloatParam, IntParam, StrParam, TheanoConfigParser, THEANO_FLAGS_DICT
  from theano.misc.cpucount import cpuCount
  from theano.misc.windows import call_subprocess_Popen, output_subprocess_Popen
  from theano.compat import maybe_add_to_os_environ_pathlist
label_desc: Use image node_id 1 to create a new ContextsParam object from inherited base classes: ConfigParam with example: obj = ContextsParam()