class_docstr: Class to help protect the environment variable properly.  Can be used as
  a context manager.
class_docstr_tok: ["Class","to","help","protect","the","environment","variable","properly",".","Can","be","used","as","a","context","manager","."]
code: def set(self, envvar, value):
      self[envvar] = value
  
imports: import collections.abc
  import contextlib
  import errno
  import os
  import re
  import stat
  import string
  import sys
  import time
  import unittest
  import warnings
  from test import support
label_desc: Use image node_id 8 for calling the EnvironmentVarGuard obj's underlying member method code with example usage: obj.set(envvar, value) without return types