class_docstr: Represents a boolean environment variable.
code: def __init__(self, name, default):
      # `default not in [True, False, None]` doesn't work because `1 in [True]`
      # (or `0 in [False]`) returns True.
      if not (default is True or default is False or default is None):
          raise ValueError(
              f"{name} default value must be one of [True, False, None]"
          )
      super().__init__(name, bool, default)
  
file_path: mlflow/mlflow/environment_variables.py
imports: import os
  from pathlib import Path
label_desc: Use image node_id 1 to create a new _BooleanEnvironmentVariable object from inherited base classes: _EnvironmentVariable with example: obj = _BooleanEnvironmentVariable(name, default)