+ r"""as_tuple(obj) -> tuple :: Convert objects to tuple.
+
+ This function returns a tuple for any object. If the object is
+ a string or any non-sequence object, it returns a tuple with the
+ single value. If the object is a sequece or a generator, it returns
+ the conversion to a tuple of it.
+
+ Example:
+
+ >>> print f("hello")
+ ('hello',)
+ >>> print f([1,2,3])
+ (1, 2, 3)
+ >>> print f([[1,2,3],[6,7,8]])
+ ([1, 2, 3], [6, 7, 8])
+ >>> print f(dict(a=1, b=2))
+ (('a', 1), ('b', 2))
+ """