import pydantic objects from the `_pydantic_compat` module (#17667)

This PR changes `from pydantic import BaseModel` to `from
synapse._pydantic_compat import BaseModel` (as well as `constr`,
`conbytes`, `conint`, `confloat`).

It allows `check_pydantic_models.py` to mock those pydantic objects only
in the synapse module, and not interfere with pydantic objects in
external dependencies.

This should solve the CI problems for #17144, which breaks because
`check_pydantic_models.py` patches pydantic models from
[scim2-models](https://scim2-models.readthedocs.io/).

/cc @DMRobertson @gotmax23
fixes #17659 


### Pull Request Checklist

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before submitting your pull request -->

* [x] Pull request is based on the develop branch
* [x] Pull request includes a [changelog
file](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#changelog).
The entry should:
- Be a short description of your change which makes sense to users.
"Fixed a bug that prevented receiving messages from other servers."
instead of "Moved X method from `EventStore` to `EventWorkerStore`.".
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* [x] [Code
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correct
(run the
[linters](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#run-the-linters))

6 files changed, 6 insertions, 39 deletions

diff --git a/synapse/rest/admin/users.py b/synapse/rest/admin/users.py

index ad515bd5a3..076994b87e 100644
--- a/synapse/rest/admin/users.py
+++ b/synapse/rest/admin/users.py
@@ -27,7 +27,7 @@ from typing import TYPE_CHECKING, Dict, List, Optional, Tuple, Union
 
 import attr
 
-from synapse._pydantic_compat import HAS_PYDANTIC_V2
+from synapse._pydantic_compat import StrictBool
 from synapse.api.constants import Direction, UserTypes
 from synapse.api.errors import Codes, NotFoundError, SynapseError
 from synapse.http.servlet import (
@@ -56,11 +56,6 @@ from synapse.types.rest import RequestBodyModel
 if TYPE_CHECKING:
     from synapse.server import HomeServer
 
-if TYPE_CHECKING or HAS_PYDANTIC_V2:
-    from pydantic.v1 import StrictBool
-else:
-    from pydantic import StrictBool
-
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/rest/client/account.py b/synapse/rest/client/account.py

index 8daa449f9e..32fa7b4ec4 100644
--- a/synapse/rest/client/account.py
+++ b/synapse/rest/client/account.py
@@ -24,18 +24,12 @@ import random
 from typing import TYPE_CHECKING, List, Optional, Tuple
 from urllib.parse import urlparse
 
-from synapse._pydantic_compat import HAS_PYDANTIC_V2
-
-if TYPE_CHECKING or HAS_PYDANTIC_V2:
-    from pydantic.v1 import StrictBool, StrictStr, constr
-else:
-    from pydantic import StrictBool, StrictStr, constr
-
 import attr
 from typing_extensions import Literal
 
 from twisted.web.server import Request
 
+from synapse._pydantic_compat import StrictBool, StrictStr, constr
 from synapse.api.constants import LoginType
 from synapse.api.errors import (
     Codes,
diff --git a/synapse/rest/client/devices.py b/synapse/rest/client/devices.py

index 8313d687b7..6a45a5d130 100644
--- a/synapse/rest/client/devices.py
+++ b/synapse/rest/client/devices.py
@@ -24,13 +24,7 @@ import logging
 from http import HTTPStatus
 from typing import TYPE_CHECKING, List, Optional, Tuple
 
-from synapse._pydantic_compat import HAS_PYDANTIC_V2
-
-if TYPE_CHECKING or HAS_PYDANTIC_V2:
-    from pydantic.v1 import Extra, StrictStr
-else:
-    from pydantic import Extra, StrictStr
-
+from synapse._pydantic_compat import Extra, StrictStr
 from synapse.api import errors
 from synapse.api.errors import NotFoundError, SynapseError, UnrecognizedRequestError
 from synapse.handlers.device import DeviceHandler
diff --git a/synapse/rest/client/directory.py b/synapse/rest/client/directory.py

index 11fdd0f7c6..98ba5c4c2a 100644
--- a/synapse/rest/client/directory.py
+++ b/synapse/rest/client/directory.py
@@ -22,17 +22,11 @@
 import logging
 from typing import TYPE_CHECKING, List, Optional, Tuple
 
-from synapse._pydantic_compat import HAS_PYDANTIC_V2
-
-if TYPE_CHECKING or HAS_PYDANTIC_V2:
-    from pydantic.v1 import StrictStr
-else:
-    from pydantic import StrictStr
-
 from typing_extensions import Literal
 
 from twisted.web.server import Request
 
+from synapse._pydantic_compat import StrictStr
 from synapse.api.errors import AuthError, Codes, NotFoundError, SynapseError
 from synapse.http.server import HttpServer
 from synapse.http.servlet import (
diff --git a/synapse/rest/client/reporting.py b/synapse/rest/client/reporting.py

index 4eee53e5a8..97bd5d8c02 100644
--- a/synapse/rest/client/reporting.py
+++ b/synapse/rest/client/reporting.py
@@ -23,7 +23,7 @@ import logging
 from http import HTTPStatus
 from typing import TYPE_CHECKING, Tuple
 
-from synapse._pydantic_compat import HAS_PYDANTIC_V2
+from synapse._pydantic_compat import StrictStr
 from synapse.api.errors import AuthError, Codes, NotFoundError, SynapseError
 from synapse.http.server import HttpServer
 from synapse.http.servlet import (
@@ -40,10 +40,6 @@ from ._base import client_patterns
 if TYPE_CHECKING:
     from synapse.server import HomeServer
 
-if TYPE_CHECKING or HAS_PYDANTIC_V2:
-    from pydantic.v1 import StrictStr
-else:
-    from pydantic import StrictStr
 
 logger = logging.getLogger(__name__)
 
diff --git a/synapse/rest/key/v2/remote_key_resource.py b/synapse/rest/key/v2/remote_key_resource.py

index 3c2028a2ad..fea0b9706d 100644
--- a/synapse/rest/key/v2/remote_key_resource.py
+++ b/synapse/rest/key/v2/remote_key_resource.py
@@ -23,17 +23,11 @@ import logging
 import re
 from typing import TYPE_CHECKING, Dict, Mapping, Optional, Set, Tuple
 
-from synapse._pydantic_compat import HAS_PYDANTIC_V2
-
-if TYPE_CHECKING or HAS_PYDANTIC_V2:
-    from pydantic.v1 import Extra, StrictInt, StrictStr
-else:
-    from pydantic import Extra, StrictInt, StrictStr
-
 from signedjson.sign import sign_json
 
 from twisted.web.server import Request
 
+from synapse._pydantic_compat import Extra, StrictInt, StrictStr
 from synapse.crypto.keyring import ServerKeyFetcher
 from synapse.http.server import HttpServer
 from synapse.http.servlet import (