[Python] Pylance type error supplying SQLAlchemy NVARCHAR length

Pylance is raising a type error when I include a length for the NVARCHAR column in the below script:

import urllib.parse
import uuid

import pandas as pd
from sqlalchemy import create_engine
from sqlalchemy.types import NVARCHAR
from sqlalchemy.dialects.mssql import UNIQUEIDENTIFIER

# CREATE DATABASE CONNECTION
connection = create_engine(
f"mssql+pyodbc:///?odbc_connect={
urllib.parse.quote_plus(
'DRIVER=' + <driver details here> + ';'
'SERVER=' + <server details here> + ';'
'DATABASE=' + <db details here> + ';'
'UID=' + <uid details here> + ';'
'PWD=' + <pwd details here> + ';'
'Authentication=' + <auth details here>
)
}"
)

# CREATE DATAFRAME
df = pd.DataFrame(
columns=['id', 'name'],
data=[
[str(uuid.uuid4()), 'hello'],
[str(uuid.uuid4()), 'world'],
[str(uuid.uuid4()), 'foo'],
[str(uuid.uuid4()), 'bar'],
[str(uuid.uuid4()), 'baz'],
]
)

# SAVE DATA
df.to_sql(
'test',
con=connection,
dtype={
'id': UNIQUEIDENTIFIER,
'name': NVARCHAR(length=1024),
},
index=False,
)



Specifically, it raises Argument of type "dict[str, type[UNIQUEIDENTIFIER[_UUID_RETURN@UNIQUEIDENTIFIER]] | NVARCHAR]" cannot be assigned to parameter "dtype" of type "DtypeArg | None" in function "to_sql".

If I remove the length parameter on NVARCHAR the error goes away, but I need to be able to specify the length.

Am I doing something wrong or is this a bug in Pyright/Pylance?

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