Python: implement Chat history, and refactor prompt config/prompt con…

…fig template (#5023)

### Motivation and Context

This PR addresses a few of our remaining urgent work items: #4856,
#4630.

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  2. What problem does it solve?
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### Description

In this PR:
- The prompt template/prompt template config is refactored to be similar
to the dotnet versions.
- The KernelPromptTemplate is introduced as the default prompt template
(will need to make it more dynamic in the future when we have other
prompt templates, like handlebars or jinja2).
- The methods related to `create_semantic_function` were removed and it
their places a method `create_function_from_prompt` was added.
- ChatHistory was introduced as a way to take over what ChatMessage was
doing. ChatHistory is passed into the complete chat/text methods.
- As of these latest changes, all unit and integration tests are
passing.
- New kernel examples were added to exercise this new code.

<!-- Describe your changes, the overall approach, the underlying design.
These notes will help understanding how your code works. Thanks! -->

### Contribution Checklist

<!-- Before submitting this PR, please make sure: -->

- [X] The code builds clean without any errors or warnings
- [X] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [X] All unit tests pass, and I have added new tests where possible
- [ ] I didn't break anyone 😄

---------

Co-authored-by: Eduard van Valkenburg <eavanvalkenburg@users.noreply.github.com>

python/README.md

@@ -33,11 +33,25 @@ kernel = sk.Kernel()
 
 # Prepare OpenAI service using credentials stored in the `.env` file
 api_key, org_id = sk.openai_settings_from_dot_env()
-kernel.add_chat_service("chat-gpt", OpenAIChatCompletion("gpt-3.5-turbo", api_key, org_id))
+kernel.add_service(
+    OpenAIChatCompletion(
+        service_id="chat-gpt",
+        ai_model_id="gpt-3.5-turbo",
+        api_key=api_key,
+        org_id=org_id
+    )
+)
 
 # Alternative using Azure:
 # deployment, api_key, endpoint = sk.azure_openai_settings_from_dot_env()
-# kernel.add_chat_service("dv", AzureChatCompletion(deployment, endpoint, api_key))
+# kernel.add_service(
+#   AzureChatCompletion(
+#       service_id="dv",
+#       deployment_name=deployment,
+#       base_url=endpoint,
+#       api_key=api_key
+#   )
+# )
 
 # Wrap your prompt in a function
 prompt = kernel.create_semantic_function("""

python/notebooks/00-getting-started.ipynb

@@ -31,20 +31,10 @@
    ]
   },
   {
-   "attachments": {},
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "## Option 1: using OpenAI\n",
-    "\n",
-    "**Step 2**: Add your [OpenAI Key](https://openai.com/product/) key to a `.env` file in the same folder (org Id only if you have multiple orgs):\n",
-    "\n",
-    "```\n",
-    "OPENAI_API_KEY=\"sk-...\"\n",
-    "OPENAI_ORG_ID=\"\"\n",
-    "```\n",
-    "\n",
-    "Use \"keyword arguments\" to instantiate an OpenAI Chat Completion service and add it to the kernel:"
+    "### Configure the service you'd like to use via the `Service` Enum."
    ]
   },
   {
@@ -53,21 +43,28 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "from semantic_kernel.connectors.ai.open_ai import OpenAIChatCompletion\n",
+    "from services import Service\n",
     "\n",
-    "api_key, org_id = sk.openai_settings_from_dot_env()\n",
-    "\n",
-    "kernel.add_chat_service(\n",
-    "    \"chat-gpt\",\n",
-    "    OpenAIChatCompletion(ai_model_id=\"gpt-3.5-turbo-1106\", api_key=api_key, org_id=org_id),\n",
-    ")"
+    "# Select a service to use for this notebook (available services: OpenAI, AzureOpenAI, HuggingFace)\n",
+    "selectedService = Service.OpenAI"
    ]
   },
   {
    "attachments": {},
    "cell_type": "markdown",
    "metadata": {},
    "source": [
+    "## Option 1: using OpenAI\n",
+    "\n",
+    "**Step 2**: Add your [OpenAI Key](https://openai.com/product/) key to a `.env` file in the same folder (org Id only if you have multiple orgs):\n",
+    "\n",
+    "```\n",
+    "OPENAI_API_KEY=\"sk-...\"\n",
+    "OPENAI_ORG_ID=\"\"\n",
+    "```\n",
+    "\n",
+    "Use \"keyword arguments\" to instantiate an OpenAI Chat Completion service and add it to the kernel:\n",
+    "\n",
     "## Option 2: using Azure OpenAI\n",
     "\n",
     "**Step 2**: Add your [Azure Open AI Service key](https://learn.microsoft.com/azure/cognitive-services/openai/quickstart?pivots=programming-language-studio) settings to a `.env` file in the same folder:\n",
@@ -87,14 +84,23 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "from semantic_kernel.connectors.ai.open_ai import AzureChatCompletion\n",
+    "service_id = None\n",
+    "if selectedService == Service.OpenAI:\n",
+    "    from semantic_kernel.connectors.ai.open_ai import OpenAIChatCompletion\n",
     "\n",
-    "deployment, api_key, endpoint = sk.azure_openai_settings_from_dot_env()\n",
+    "    api_key, org_id = sk.openai_settings_from_dot_env()\n",
+    "    service_id = \"chat-gpt\"\n",
+    "    kernel.add_service(\n",
+    "        OpenAIChatCompletion(service_id=service_id, ai_model_id=\"gpt-3.5-turbo-1106\", api_key=api_key, org_id=org_id),\n",
+    "    )\n",
+    "elif selectedService == Service.AzureOpenAI:\n",
+    "    from semantic_kernel.connectors.ai.open_ai import AzureChatCompletion\n",
     "\n",
-    "kernel.add_chat_service(\n",
-    "    \"chat_completion\",\n",
-    "    AzureChatCompletion(deployment_name=deployment, endpoint=endpoint, api_key=api_key),\n",
-    ")"
+    "    deployment, api_key, endpoint = sk.azure_openai_settings_from_dot_env()\n",
+    "    service_id = \"chat_completion\"\n",
+    "    kernel.add_service(\n",
+    "        AzureChatCompletion(service_id=service_id, deployment_name=deployment, endpoint=endpoint, api_key=api_key),\n",
+    "    )"
    ]
   },
   {
@@ -113,10 +119,27 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "plugin = kernel.import_semantic_plugin_from_directory(\"../../samples/plugins\", \"FunPlugin\")\n",
+    "try:\n",
+    "    plugin = kernel.import_plugin_from_prompt_directory(service_id, \"../../samples/plugins\", \"FunPlugin\")\n",
+    "except ValueError as e:\n",
+    "    # Don't fail if we try to add the plug in again\n",
+    "    # This is just for the sake of the example\n",
+    "    # Once the plugin has been added to the kernel it will fail\n",
+    "    # to add it again, if this cell is run multiple times without\n",
+    "    # restarting the kernel\n",
+    "    pass"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
     "joke_function = plugin[\"Joke\"]\n",
     "\n",
-    "print(await joke_function(\"time travel to dinosaur age\"))"
+    "joke = await kernel.invoke(joke_function, sk.KernelArguments(input=\"time travel to dinosaur age\", style=\"super silly\"))\n",
+    "print(joke)"
    ]
   }
  ],

python/notebooks/01-basic-loading-the-kernel.ipynb

@@ -34,29 +34,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "import semantic_kernel as sk\n",
-    "from semantic_kernel.connectors.ai.open_ai import (\n",
-    "    AzureChatCompletion,\n",
-    "    OpenAIChatCompletion,\n",
-    ")"
-   ]
-  },
-  {
-   "attachments": {},
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "You can instantiate the kernel in a few ways, depending on your use case."
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 2,
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "# Simple instance\n",
-    "kernel_1 = sk.Kernel()"
+    "import semantic_kernel as sk"
    ]
   },
   {
@@ -66,7 +44,7 @@
    "source": [
     "When using the kernel for AI requests, the kernel needs some settings like URL and credentials to the AI models.\n",
     "\n",
-    "The SDK currently supports OpenAI and Azure OpenAI, other services will be added over time.\n",
+    "The SDK currently supports OpenAI and Azure OpenAI, among other connectors.\n",
     "\n",
     "If you need an Azure OpenAI key, go [here](https://learn.microsoft.com/en-us/azure/cognitive-services/openai/quickstart?pivots=rest-api)."
    ]
@@ -77,39 +55,10 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "kernel = sk.Kernel()\n",
+    "from services import Service\n",
     "\n",
-    "kernel.add_chat_service(  # We are adding a text service\n",
-    "    \"Azure_curie\",  # The alias we can use in prompt templates' config.json\n",
-    "    AzureChatCompletion(\n",
-    "        deployment_name=\"my-finetuned-Curie\",  # Azure OpenAI *Deployment name*\n",
-    "        endpoint=\"https://contoso.openai.azure.com/\",  # Azure OpenAI *Endpoint*\n",
-    "        api_key=\"...your Azure OpenAI Key...\",  # Azure OpenAI *Key*\n",
-    "    ),\n",
-    ")\n",
-    "\n",
-    "kernel.add_chat_service(  # We are adding a text service\n",
-    "    \"OpenAI_chat_gpt\",  # The alias we can use in prompt templates' config.json\n",
-    "    OpenAIChatCompletion(\n",
-    "        ai_model_id=\"gpt-3.5-turbo\",  # OpenAI Model Name\n",
-    "        api_key=\"...your OpenAI API Key...\",  # OpenAI API key\n",
-    "        org_id=\"...your OpenAI Org ID...\",  # *optional* OpenAI Organization ID\n",
-    "    ),\n",
-    ")"
-   ]
-  },
-  {
-   "attachments": {},
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "When working with multiple services and multiple models, the **first service** defined\n",
-    "is also the \"**default**\" used in these scenarios:\n",
-    "\n",
-    "* a prompt configuration doesn't specify which AI service to use\n",
-    "* a prompt configuration requires a service unknown to the kernel\n",
-    "\n",
-    "The default can be set and changed programmatically:"
+    "# Select a service to use for this notebook (available services: OpenAI, AzureOpenAI, HuggingFace)\n",
+    "selectedService = Service.OpenAI"
    ]
   },
   {
@@ -118,7 +67,25 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "kernel.set_default_text_completion_service(\"Azure_curie\")"
+    "kernel = sk.Kernel()\n",
+    "\n",
+    "service_id = None\n",
+    "if selectedService == Service.OpenAI:\n",
+    "    from semantic_kernel.connectors.ai.open_ai import OpenAIChatCompletion\n",
+    "\n",
+    "    api_key, org_id = sk.openai_settings_from_dot_env()\n",
+    "    service_id = \"oai_chat_gpt\"\n",
+    "    kernel.add_service(\n",
+    "        OpenAIChatCompletion(service_id=service_id, ai_model_id=\"gpt-3.5-turbo-1106\", api_key=api_key, org_id=org_id),\n",
+    "    )\n",
+    "elif selectedService == Service.AzureOpenAI:\n",
+    "    from semantic_kernel.connectors.ai.open_ai import AzureChatCompletion\n",
+    "\n",
+    "    deployment, api_key, endpoint = sk.azure_openai_settings_from_dot_env()\n",
+    "    service_id = \"aoai_chat_completion\"\n",
+    "    kernel.add_service(\n",
+    "        AzureChatCompletion(service_id=service_id, deployment_name=deployment, endpoint=endpoint, api_key=api_key),\n",
+    "    )"
    ]
   },
   {