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New features:
* Consistent parsing in terms of true python representation of date string. See 281
* Added support for Bangla, Bulgarian and Hindi languages.
Improvements:
* Major bug fixes related to parser and system's locale. See 277, 282
* Type check for timezone arguments in settings. see 267
* Pinned dependencies' versions in requirements. See 265
* Improved support for cn, es, dutch languages. See 274, 272, 285
Packaging:
* Make calendars extras to be used at the time of installation if need to use calendars feature.