fix failing test and rewrite comment

Author: tybug

hypothesis-python/src/hypothesis/_settings.py

@@ -440,8 +440,7 @@ def _validate_database(db: "ExampleDatabase") -> "ExampleDatabase":
         return db
     raise InvalidArgument(
         "Arguments to the database setting must be None or an instance of "
-        f"ExampleDatabase.  Try passing database=ExampleDatabase({db!r}), or "
-        "construct and use one of the specific subclasses in "
+        "ExampleDatabase. Try using one of the specific subclasses in "
         "hypothesis.database"
     )
 

hypothesis-python/tests/nocover/test_flatmap.py

@@ -13,7 +13,7 @@
 import pytest
 
 from hypothesis import HealthCheck, assume, given, settings
-from hypothesis.database import ExampleDatabase
+from hypothesis.database import InMemoryExampleDatabase
 from hypothesis.strategies import (
     booleans,
     builds,
@@ -55,7 +55,7 @@ def test_flatmap_retrieve_from_db():
     track = []
 
     @given(floats(0, 1).flatmap(lambda x: lists(just(x))))
-    @settings(database=ExampleDatabase())
+    @settings(database=InMemoryExampleDatabase())
     def record_and_test_size(xs):
         if sum(xs) >= 1:
             track.append(xs)