fix(python-aiohttp): add python_dateutil to generated requirements so dates are deserialized (#25449)

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Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

Author: khayashi4337

modules/openapi-generator/src/main/resources/python-aiohttp/requirements.mustache

@@ -7,6 +7,7 @@ connexion[aiohttp,swagger-ui] <= 2.3.0; python_version=="3.5" or python_version=
 werkzeug == 0.16.1; python_version=="3.5" or python_version=="3.4"
 swagger-ui-bundle == 0.0.9
 aiohttp_jinja2 == 1.5.0
+python_dateutil >= 2.6.0
 {{#featureCORS}}
 aiohttp_cors >= 0.7.0
 {{/featureCORS}}

modules/openapi-generator/src/main/resources/python-aiohttp/setup.mustache

@@ -17,6 +17,7 @@ REQUIRES = [
     "connexion==2.14.1",
     "swagger-ui-bundle==0.0.9",
     "aiohttp_jinja2==1.5.0",
+    "python_dateutil>=2.6.0",
 ]
 
 setup(

modules/openapi-generator/src/test/java/org/openapitools/codegen/python/AbstractPythonConnexionServerCodegenTest.java

@@ -558,4 +558,15 @@ public void testFreeFormAndAnyTypeParametersDoNotCallFromDict() throws IOExcepti
             FileUtils.deleteDirectory(flaskComposedOutput);
         }
     }
+
+    @Test(description = "python-aiohttp generated requirements.txt and setup.py declare python_dateutil so util.deserialize_date/datetime actually parse dates")
+    public void testAiohttpRequirementsIncludePythonDateutil() throws IOException {
+        Path aiohttpDir = generateOutputDir("python-aiohttp", Collections.emptyMap());
+        Path aiohttpRequirements = aiohttpDir.resolve("requirements.txt");
+        Path aiohttpSetupPy = aiohttpDir.resolve("setup.py");
+        assertFileExists(aiohttpRequirements);
+        assertFileExists(aiohttpSetupPy);
+        assertFileContains(aiohttpRequirements, "python_dateutil >= 2.6.0");
+        assertFileContains(aiohttpSetupPy, "python_dateutil>=2.6.0");
+    }
 }

samples/server/petstore/python-aiohttp-srclayout/requirements.txt

@@ -7,4 +7,5 @@ connexion[aiohttp,swagger-ui] <= 2.3.0; python_version=="3.5" or python_version=
 werkzeug == 0.16.1; python_version=="3.5" or python_version=="3.4"
 swagger-ui-bundle == 0.0.9
 aiohttp_jinja2 == 1.5.0
+python_dateutil >= 2.6.0
 Flask < 2.3

samples/server/petstore/python-aiohttp-srclayout/setup.py

@@ -17,6 +17,7 @@
     "connexion==2.14.1",
     "swagger-ui-bundle==0.0.9",
     "aiohttp_jinja2==1.5.0",
+    "python_dateutil>=2.6.0",
 ]
 
 setup(