[Answered ]-Faster Django Admin Paginator: Cannot get this Django snippet to work

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I think we can drag that paginator into the django 1.10 world (hopefullly not kicking and screaming) like this:

from django.core.paginator import Paginator
from django.core.cache import cache
from django.utils.functional import cached_property
from django.db import connection

class FasterAdminPaginator(Paginator):
    @cached_property
    def count(self):
        try:
            if not self.object_list.query.where:
                # estimates COUNT: https://djangosnippets.org/snippets/2593/
                cursor = connection.cursor()
                cursor.execute("SELECT reltuples FROM pg_class WHERE relname = %s",
                    [self.object_list.query.model._meta.db_table])
                print 'Using the reltuples'

                ret = int(cursor.fetchone()[0])
            else :
                return self.object_list.count()
        except :
            import traceback
            traceback.print_exc()
            # AttributeError if object_list has no count() method.
            return len(self.object_list)

Thakns to cached_property the extensive caching code used in the original snippets are no longer needed. For completeness, this is what the relevent section of django.core.paginator.Paginator looks like

@cached_property
def count(self):
    """
    Returns the total number of objects, across all pages.
    """
    try:
        return self.object_list.count()
    except (AttributeError, TypeError):
        # AttributeError if object_list has no count() method.
        # TypeError if object_list.count() requires arguments
        # (i.e. is of type list).
        return len(self.object_list)
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