Extending django_filters DateTimeFromToRangeFilter to support postgres datetime tstzrange fields with the available lookup names.

django_filters_postgres_datetime_range.py

from django.contrib.postgres.forms import DateTimeRangeField
from django.core.exceptions import ImproperlyConfigured
from django_filters import DateTimeFromToRangeFilter as DateTimeFromToRangeGenericFilter


class DateTimeTZFromToRangeFilter(DateTimeFromToRangeGenericFilter):
    field_class = DateTimeRangeField
    lookup_names = {
        'contained_by', 'contains', 'overlap', 'fully_lt', 'full_gt',
        'not_lt', 'not_gt', 'adjacent_to',
    }
    default_lookup_expr = 'contained_by'

    def _get_lookup_expr(self):
        if self.lookup_expr in self.lookup_names:
            return self.lookup_expr
        raise ImproperlyConfigured(
            f'{self.__class__.__name__} "lookup_expr" has to be one of '
            f'"{repr(self.lookup_names)}".',
        )

    def filter(self, qs, value):
        if value:
            qs = self.get_method(qs)
            lookup = f'{self.field_name}'
            if all([value.lower is not None, value.upper is not None]):
                lookup += f'__{self._get_lookup_expr()}'
            else:
                if value.lower is not None:
                    lookup += '__not_lt'
                if value.upper is not None:
                    lookup += '__not_gt'
            qs = qs(**{lookup: value})
            if self.distinct:
                qs = qs.distinct()
        return qs