class_docstr: This is to maintain a globally-accessible context environment that is visible to everywhere.
  
  To initiate::
  
      with ContextStack(namespace, value):
          ...
  
  Inside the context, you can access the nearest value put into ``with``::
  
      get_current_context(namespace)
  
  Notes
  -----
  :class:`ContextStack` is not multi-processing safe. Also, the values will get cleared for a new process.
class_docstr_tok: ["This","is","to","maintain","a","globally-accessible","context","environment","that","is","visible","to","everywhere",".","To","initiate",":",":","with","ContextStack","(","namespace",",","value",")",":","...","Inside","the","context",",","you","can","access","the","nearest","value","put","into","``","with","``",":",":","get_current_context","(","namespace",")","Notes","--","--","-",":","class",":","`","ContextStack","`","is","not","multi-processing","safe",".","Also",",","the","values","will","get","cleared","for","a","new","process","."]
code: def pop(cls, key: str) -> Any:
      if not cls._stack[key]:
          raise NoContextError(f"Context with key {key} is empty.")
      return cls._stack[key].pop()
  
imports: from __future__ import annotations
  import logging
  from collections import defaultdict
  from typing import Any, List, cast
label_desc: Use image node_id 5 for calling the ContextStack obj's underlying member method code with example usage: obj.pop(cls, key) and returns: cls