diff --git a/django_mongodb/base.py b/django_mongodb/base.py
index 07a2866..e9a0443 100644
--- a/django_mongodb/base.py
+++ b/django_mongodb/base.py
@@ -71,8 +71,6 @@ class DatabaseWrapper(BaseDatabaseWrapper):
         "iendswith": "LIKE UPPER(%s)",
     }
 
-    connection: MongoClient = None
-
     SchemaEditorClass = DatabaseSchemaEditor
     # Classes instantiated in __init__().
     client_class = DatabaseClient
diff --git a/django_mongodb/compiler.py b/django_mongodb/compiler.py
index c5bbaa0..3b69758 100644
--- a/django_mongodb/compiler.py
+++ b/django_mongodb/compiler.py
@@ -2,7 +2,7 @@
 from itertools import chain
 
 from django.db.models.sql.compiler import (
-    SQLCompiler as BaseSQLCompiler,
+    SQLCompiler as BaseSQLCompiler, cursor_iter,
 )
 from django.db.models.sql.compiler import (
     SQLInsertCompiler as BaseSQLInsertCompiler,
@@ -186,7 +186,6 @@ def results_iter(
         fields = [s[0] for s in self.select[0 : self.col_count]]
         converters = self.get_converters(fields)
         rows = chain.from_iterable(results)
-        # Temporary mapping of dict to tuple, until we move this to 'project'
         _row_tuples = []
         cols = self.select[0 : self.col_count]
         for row in rows:
@@ -202,18 +201,6 @@ def results_iter(
             yield row
 
 
-def cursor_iter(cursor, sentinel, col_count, itersize):
-    """
-    Yield blocks of rows from a cursor and ensure the cursor is closed when
-    done.
-    """
-    try:
-        for rows in iter((lambda: cursor.fetchmany(itersize)), sentinel):
-            yield rows if col_count is None else [r[:col_count] for r in rows]
-    finally:
-        cursor.close()
-
-
 class SQLDeleteCompiler(SQLCompiler):
     def as_operation(self, with_limits=True, with_col_aliases=False):
         opts = self.query.get_meta()
@@ -229,8 +216,6 @@ class SQLInsertCompiler(SQLCompiler, BaseSQLInsertCompiler):
     compiler = "SQLInsertCompiler"
 
     def as_operation(self):
-        # We don't need quote_name_unless_alias() here, since these are all
-        # going to be column names (so we can avoid the extra overhead).
         opts = self.query.get_meta()
         fields = self.query.fields or [opts.pk]