Remove an unused early-out test from the critical path for
dict and set lookups.

When the strings already have matching lengths, kinds, and hashes,
there is no additional information gained by checking the first
characters (the probability of a mismatch is already known to
be less than 1 in 2**64).

prefix from two attributes and two methods of History class.

instead of 6, to reduce the risk of filename collision. The entropy was reduced
when uppercase letters were removed from the charset used to generate random
characters.

Increasing test coverage of ftplib. Patch by Muhammad Jehanzeb

Issue #18680: JSONDecoder should document that it raises a ValueError
  for malformed data

Issue #18680: JSONDecoder should document that it raises a ValueError
  for malformed data

Issue #18680: JSONDecoder should document that it raises a ValueError
  for malformed data

Issue #18680: JSONDecoder should document that it raises a ValueError
  for malformed data

Issue #18585: Add :func:`textwrap.shorten` to collapse and truncate a piece of text to a given length.

importlib.import_module() include the name of the module when the
'package' argument is missing but needed.

Patch by Neil Schemenauer, minimally modified.

(re-apply after fix for tkinter-related crash)