def _deprecateAttribute(proxy, name, version, message):
    """
    Mark a module-level attribute as being deprecated.

    @type proxy: L{_ModuleProxy}
    @param proxy: The module proxy instance proxying the deprecated attributes

    @type name: C{str}
    @param name: Attribute name

    @type version: L{incremental.Version}
    @param version: Version that the attribute was deprecated in

    @type message: C{str}
    @param message: Deprecation message
    """
    _module = object.__getattribute__(proxy, '_module')
    attr = _DeprecatedAttribute(_module, name, version, message)
    # Add a deprecated attribute marker for this module's attribute. When this
    # attribute is accessed via _ModuleProxy a warning is emitted.
    _deprecatedAttributes = object.__getattribute__(
        proxy, '_deprecatedAttributes')
    _deprecatedAttributes[name] = attr

    Mark a module-level attribute as being deprecated.

    @type proxy: L{_ModuleProxy}
    @param proxy: The module proxy instance proxying the deprecated attributes

    @type name: C{str}
    @param name: Attribute name

    @type version: L{incremental.Version}
    @param version: Version that the attribute was deprecated in

    @type message: C{str}
    @param message: Deprecation message
    
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/deprecate.py