def _getDeprecationDocstring(version, replacement=None):
    """
    Generate an addition to a deprecated object's docstring that explains its
    deprecation.

    @param version: the version it was deprecated.
    @type version: L{incremental.Version}

    @param replacement: The replacement, if specified.
    @type replacement: C{str} or callable

    @return: a string like "Deprecated in Twisted 27.2.0; please use
        twisted.timestream.tachyon.flux instead."
    """
    doc = "Deprecated in %s" % (getVersionString(version),)
    if replacement:
        doc = "%s; %s" % (doc, _getReplacementString(replacement))
    return doc + "."

    Generate an addition to a deprecated object's docstring that explains its
    deprecation.

    @param version: the version it was deprecated.
    @type version: L{incremental.Version}

    @param replacement: The replacement, if specified.
    @type replacement: C{str} or callable

    @return: a string like "Deprecated in Twisted 27.2.0; please use
        twisted.timestream.tachyon.flux instead."
    
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/deprecate.py