Drop Django 3.0, 3.1, 3.2. Drop Python 3.7.

anymail/__init__.py

@@ -4,14 +4,3 @@ __all__ = [
     "VERSION",
     "__version__",
 ]
-
-try:
-    import django
-except ImportError:
-    # (don't require django just to get package version)
-    pass
-else:
-    if django.VERSION < (3, 2, 0):
-        # (No longer required -- and causes deprecation warning -- in Django 3.2+)
-        default_app_config = "anymail.apps.AnymailBaseConfig"
-        __all__.append("default_app_config")

anymail/_version.py

@@ -2,6 +2,6 @@
 # Instead, load version info from the package root.
 
 #: major.minor or major.minor.patch (optionally with .devN suffix)
-__version__ = "11.1"
+__version__ = "12.0.dev0"
 
 VERSION = __version__.split(",")