code: def is_plot_key(key: str) -> bool:
      """Returns true if key is a plot key."""
      # We need to check for suffixes here because metrics may have prefixes based
      # on multiple labels and/or heads.
      for suffix in _PLOT_SUFFIXES:
          if key.endswith(suffix):
              return True
      return False
  
imports: from typing import Optional
label_desc: Use image node_id 5 for calling a global function with example usage: is_plot_key(key) and returns: False, True