Fix typo reported to python-docs.

Doc/tut/tut.tex

@@ -1826,7 +1826,7 @@ List comprehensions provide a concise way to create lists without resorting
 to use of \function{map()}, \function{filter()} and/or \keyword{lambda}.
 The resulting list definition tends often to be clearer than lists built
 using those constructs.  Each list comprehension consists of an expression
-following by a \keyword{for} clause, then zero or more \keyword{for} or
+followed by a \keyword{for} clause, then zero or more \keyword{for} or
 \keyword{if} clauses.  The result will be a list resulting from evaluating
 the expression in the context of the \keyword{for} and \keyword{if} clauses
 which follow it.  If the expression would evaluate to a tuple, it must be