class_docstr: Temporarily replace a module in sys.modules with an empty namespace
code: def __enter__(self):
      mod_name = self.mod_name
      try:
          self._saved_module.append(sys.modules[mod_name])
      except KeyError:
          pass
      sys.modules[mod_name] = self.module
      return self
  
imports: import sys
  import importlib.machinery
  import importlib.util
  import io
  import os
label_desc: Use image node_id 2 for calling the _TempModule obj's underlying member method code with example usage: obj.__enter__() and returns: self