Replace periods with '_DOT_' in Python enum member names (#21372)

This is relevant for enums whose values are floats since without this
step the enum is syntactically invalid.

See: #21322

Author: pcaisse

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractPythonCodegen.java

@@ -1061,6 +1061,8 @@ public void setMapNumberTo(String mapNumberTo) {
     }
 
     public String toEnumVariableName(String name, String datatype) {
+        name = name.replace(".", "_DOT_");
+
         if ("int".equals(datatype)) {
             return "NUMBER_" + name.replace("-", "MINUS_");
         }

modules/openapi-generator/src/test/resources/3_0/enum_float.yaml

@@ -0,0 +1,33 @@
+openapi: 3.0.0
+info:
+  title: Sample API
+  description: API description in Markdown.
+  version: 1.0.0
+paths:
+  /pony-sizes:
+    get:
+      summary: Returns all pony sizes.
+      description: Optional extended description in Markdown.
+      responses:
+        200:
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/PonySizes'
+components:
+  schemas:
+    PonySizes:
+      type: object
+      properties:
+        type:
+          $ref: '#/components/schemas/Type'
+    Type:
+      type: float
+      enum:
+        - 2.0
+        - 1.0
+        - 0.5
+        - 0.25