Fix file upload conditional using wire_value instead of parameter name

The generated code was checking `if LogoFile is not None` instead of
`if logo_file is not None`, causing mypy "name not defined" errors when
the API wire name differed from the Python snake_case parameter name.

Changed to use `key.name.snake_case.safe_name` (the parameter name)
instead of `key.wire_value` (the API field name) in the conditional.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: tjb9dc

generators/python/sdk/versions.yml

@@ -1,5 +1,15 @@
 # yaml-language-server: $schema=../../../fern-versions-yml.schema.json
 # For unreleased changes, use unreleased.yml
+- version: 4.43.1
+  changelogEntry:
+    - summary: |
+        Fix file upload conditional check using wire_value instead of snake_case parameter name,
+        which caused mypy "name not defined" errors when the API field name differed from the
+        Python parameter name (e.g., `MyFile` vs `my_file`).
+      type: fix
+  createdAt: "2025-12-08"
+  irVersion: 61
+
 - version: 4.43.0
   changelogEntry:
     - summary: |

generators/python/src/fern_python/generators/sdk/client_generator/request_body_parameters/file_upload_request_body_parameters.py

@@ -195,7 +195,7 @@ def write_file_property(writer: AST.NodeWriter, file_property: ir_types.FileProp
                                 write_file_property(writer, property_as_union.value)
                                 writer.write("} ")
                                 writer.write_line(
-                                    f"if {property_as_union.value.get_as_union().key.wire_value} is not None "
+                                    f"if {self._get_file_property_name(property_as_union.value)} is not None "
                                 )
                                 writer.write_line("else {}")
                             writer.write_line("),")