Add documentation of Integer index

Author: trevorkarn

src/sage/sets/family.py

@@ -1346,7 +1346,7 @@ def __setstate__(self, state):
 class EnumeratedFamily(LazyFamily):
     r"""
     :class:`EnumeratedFamily` turns an enumerated set ``c`` into a family
-    indexed by the set `\{0,\dots, |c|-1\}`.
+    indexed by the set `\{0,\dots, |c|-1\}` or ``ZZ``.
 
     Instances should be created via the :func:`Family` factory. See its
     documentation for examples and tests.
@@ -1374,6 +1374,8 @@ def __init__(self, enumset):
             True
             sage: Family(Permutations()).keys()
             Non negative integers
+            sage: type(Family(ZZ))
+            <class 'sage.sets.family.EnumeratedFamily_with_category'>
         """
         if enumset.cardinality() == Infinity:
             baseset = NonNegativeIntegers()