Log Message:
py-djangorestframework: updated to 3.7.3

Version 3.7.3:
Fix AppRegistryNotReady error importing contrib.auth views

Version 3.7.2:
Fixed Django 2.1 compatibility due to removal of \ 
django.contrib.auth.login()/logout() views.
Add missing import for TextLexer.
Adding examples and documentation for caching
Include date and date-time format for schema generation
Use triple backticks for markdown code blocks
Interactive docs - make bottom sidebar items sticky
Clarify pagination system check
Stop JSONBoundField mangling invalid JSON
Have JSONField render as textarea in Browsable API
Schema: Exclude OPTIONS/HEAD for ViewSet actions
Fix ordering for dotted sources
Fix: Fields with allow_null=True should imply a default serialization value
Ensure Location header is strictly a 'str', not subclass.
Add import to example in api-guide/parsers
Catch OverflowError for "out of range" datetimes
Add djangorestframework-rapidjson to third party packages
Increase test coverage for drf_create_token command
Add trove classifier for Python 3.6 support.
Add pip cache support to the Travis CI configuration
Rename [wheel] section to [bdist_wheel] as the former is legacy
Fix invalid escape sequence deprecation warnings
Add interactive docs error template
Add rounding parameter to DecimalField
Fix all BytesWarning caught during tests
Use dict and set literals instead of calls to dict() and set()
Change ImageField validation pattern, use validators from DjangoImageField
Fix processing unicode symbols in query_string by Python 2