Closes #14343: avoid shadowing builtin input() in example code.

Doc/library/re.rst

@@ -1136,7 +1136,7 @@ creates a phonebook.
 First, here is the input.  Normally it may come from a file, here we are using
 triple-quoted string syntax:
 
-   >>> input = """Ross McFluff: 834.345.1254 155 Elm Street
+   >>> text = """Ross McFluff: 834.345.1254 155 Elm Street
    ...
    ... Ronald Heathmore: 892.345.3428 436 Finley Avenue
    ... Frank Burger: 925.541.7625 662 South Dogwood Way
@@ -1150,7 +1150,7 @@ into a list with each nonempty line having its own entry:
 .. doctest::
    :options: +NORMALIZE_WHITESPACE
 
-   >>> entries = re.split("\n+", input)
+   >>> entries = re.split("\n+", text)
    >>> entries
    ['Ross McFluff: 834.345.1254 155 Elm Street',
    'Ronald Heathmore: 892.345.3428 436 Finley Avenue',