zope.datetime 4.3.0

Drop support for Python 3.4.

Add support for Python 3.7, 3.8 and 3.9.

Prevent a DeprecationWarning in Python 3.8+ when using a parameter for iso8601_date, rfc850_date, or rfc1123_date which has to be converted via its __int__ method.

Remove support for guessing the timezone name when a timestamp exceeds the value supported by Python’s localtime function. On platforms with a 32-bit time_t, this would involve parsed values that do not specify a timezone and are past the year 2038. Now the underlying exception will be propagated. Previously an undocumented heuristic was used. This is not expected to be a common issue; Windows, as one example, always uses a 64-bit time_t, even on 32-bit platforms. See https://github.com/zopefoundation/zope.datetime/issues/4

Use true division on Python 2 to match Python 3, in case certain parameters turn out to be integers instead of floating point values. This is not expected to be user-visible, but it can arise in artificial tests of internal functions.

Add support for Python 3.5 and 3.6.

Drop support for Python 2.6, 3.2 and 3.3.

Add support for PyPy and PyPy3.

Add support for Python 3.4.

Add support for testing on Travis.

Add support for Python 3.2 and 3.3.

Drop support for Python 2.4 and 2.5.

Add test cases from LP #139360 (all passed without modification to the parse function).

Remove unneeded zope.testing dependency.

Initial release as a separate project.