Nested `Model` model definition raises "Type variable cannot be used as an expression" in mypy with plugin

[selimb]

Bug

Output of python -c "import pydantic.utils; print(pydantic.utils.version_info())":

             pydantic version: 1.6.1
            pydantic compiled: False
                 install path: D:\sand\pydantic-nested\.venv\Lib\site-packages\pydantic
               python version: 3.7.6 (tags/v3.7.6:43364a7ae0, Dec 18 2019, 23:46:00) [MSC v.1916 32 bit (Intel)]
                     platform: Windows-10-10.0.19559-SP0
     optional deps. installed: ['typing-extensions']

Additionally, I'm using mypy==0.782 (latest as of today).

# bug.py
import pydantic

class Job(pydantic.BaseModel):
    class Model(pydantic.BaseModel):
        id: str
        md5: str

    model: Model

Job.Model  # error on this line

# setup.cfg
[mypy]
plugins = pydantic.mypy

$ mypy bug.py 
bug.py:10: error: Type variable "Article.Model" cannot be used as an expression
Found 1 error in 1 file (checked 1 source file)

If I rename Model to anything else, the mypy error disappears.

[selimb]

Believe I've found the fix. Will submit PR shortly.