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Co-authored-by: cubic-dev-ai[bot] <191113872+cubic-dev-ai[bot]@users.noreply.github.com>

Author: noordawod

samples/client/petstore/kotlin-modelMutable/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt

@@ -105,6 +105,12 @@ open class ApiClient(val baseUrl: String, val client: Call.Factory = defaultClie
         var accessToken: String? = null
         const val BASE_URL_KEY: String = "org.openapitools.client.baseUrl"
 
+        @Deprecated(
+          message = "Please use the capitalized constant `BASE_URL_KEY` instead.",
+          replaceWith = ReplaceWith("BASE_URL_KEY")
+        )
+        const val baseUrlKey: String = BASE_URL_KEY
+
         @JvmStatic
         val defaultClient: OkHttpClient by lazy {
             builder.build()