From d1b69f0d4d9a1dc501beebb329efab33e4c92b58 Mon Sep 17 00:00:00 2001
From: Justin Sexton <justinsexton.dev@gmail.com>
Date: Tue, 29 Dec 2020 00:25:23 -0600
Subject: [PATCH] Fixed issue causing KeyError to be raised when building
 schema from multiple `BaseModel` with the same names declared in separate
 classes (#1912)

---
 changes/1912-JSextonn.md |  1 +
 pydantic/schema.py       |  2 +-
 tests/test_schema.py     | 16 ++++++++++++++++
 3 files changed, 18 insertions(+), 1 deletion(-)
 create mode 100644 changes/1912-JSextonn.md

diff --git a/changes/1912-JSextonn.md b/changes/1912-JSextonn.md
new file mode 100644
index 00000000000..5225db4ba25
--- /dev/null
+++ b/changes/1912-JSextonn.md
@@ -0,0 +1 @@
+Fixed issue causing KeyError to be raised when building schema from multiple `BaseModel` with the same names declared in separate classes.
\ No newline at end of file
diff --git a/pydantic/schema.py b/pydantic/schema.py
index e51d74ce123..c0ca0a41204 100644
--- a/pydantic/schema.py
+++ b/pydantic/schema.py
@@ -395,7 +395,7 @@ def get_flat_models_from_models(models: Sequence[Type['BaseModel']]) -> TypeMode
 
 
 def get_long_model_name(model: TypeModelOrEnum) -> str:
-    return f'{model.__module__}__{model.__name__}'.replace('.', '__')
+    return f'{model.__module__}__{model.__qualname__}'.replace('.', '__')
 
 
 def field_type_schema(
diff --git a/tests/test_schema.py b/tests/test_schema.py
index ddea9ede3cf..1b517040063 100644
--- a/tests/test_schema.py
+++ b/tests/test_schema.py
@@ -2097,3 +2097,19 @@ class Model(BaseModel):
         'properties': {'a': {'title': 'A', 'type': 'string'}},
         'required': ['a'],
     }
+
+
+def test_multiple_nested_model_declarations_do_not_raise_error():
+    class ModelOne(BaseModel):
+        class NestedModel(BaseModel):
+            a: float
+
+        nested: NestedModel
+
+    class ModelTwo(BaseModel):
+        class NestedModel(BaseModel):
+            b: float
+
+        nested: NestedModel
+
+    schema([ModelOne, ModelTwo])