Document that hour in datetime.time ctor is optional parameter.

Thanks to Sean Munkel from docs@

Doc/library/datetime.rst

@@ -1154,7 +1154,7 @@ Using datetime with tzinfo:
 A time object represents a (local) time of day, independent of any particular
 day, and subject to adjustment via a :class:`tzinfo` object.
 
-.. class:: time(hour[, minute[, second[, microsecond[, tzinfo]]]])
+.. class:: time([hour[, minute[, second[, microsecond[, tzinfo]]]]])
 
    All arguments are optional.  *tzinfo* may be ``None``, or an instance of a
    :class:`tzinfo` subclass.  The remaining arguments may be ints or longs, in the