Update examples to prevent confusing missing _type warning (#1391)

The YAML and JSON examples of prompt serialization now give a strange
`No '_type' key found, defaulting to 'prompt'` message when you try to
run them yourself or copy the format of the files. The reason for this
harmless warning is that the _type key was not in the config files,
which means they are parsed as a standard prompt.

This could be confusing to new users (like it was confusing to me after
upgrading from 0.0.85 to 0.0.86+ for my few_shot prompts that needed a
_type added to the example_prompt config), so this update includes the
_type key just for clarity.

Obviously this is not critical as the warning is harmless, but it could
be confusing to track down or be interpreted as an error by a new user,
so this update should resolve that.

docs/modules/prompts/examples/example_prompt.json

@@ -1,4 +1,5 @@
 {
+    "_type": "prompt",
     "input_variables": ["input", "output"],
     "template": "Input: {input}\nOutput: {output}" 
 }

docs/modules/prompts/examples/few_shot_prompt.json

@@ -3,6 +3,7 @@
     "input_variables": ["adjective"],
     "prefix": "Write antonyms for the following words.",
     "example_prompt": {
+        "_type": "prompt",
         "input_variables": ["input", "output"],
         "template": "Input: {input}\nOutput: {output}"
     },

docs/modules/prompts/examples/few_shot_prompt.yaml

@@ -4,6 +4,7 @@ input_variables:
 prefix: 
     Write antonyms for the following words.
 example_prompt:
+    _type: prompt
     input_variables:
         ["input", "output"]
     template:

docs/modules/prompts/examples/few_shot_prompt_examples_in.json

@@ -3,6 +3,7 @@
     "input_variables": ["adjective"],
     "prefix": "Write antonyms for the following words.",
     "example_prompt": {
+        "_type": "prompt",
         "input_variables": ["input", "output"],
         "template": "Input: {input}\nOutput: {output}"
     },

docs/modules/prompts/examples/few_shot_prompt_yaml_examples.yaml

@@ -4,6 +4,7 @@ input_variables:
 prefix: 
     Write antonyms for the following words.
 example_prompt:
+    _type: prompt
     input_variables:
         ["input", "output"]
     template:

docs/modules/prompts/examples/prompt_serialization.ipynb

@@ -58,6 +58,7 @@
      "name": "stdout",
      "output_type": "stream",
      "text": [
+      "_type: prompt\r\n",
       "input_variables:\r\n",
       "    [\"adjective\", \"content\"]\r\n",
       "template: \r\n",
@@ -108,6 +109,7 @@
      "output_type": "stream",
      "text": [
       "{\r\n",
+      "    \"_type\": \"prompt\",\r\n",
       "    \"input_variables\": [\"adjective\", \"content\"],\r\n",
       "    \"template\": \"Tell me a {adjective} joke about {content}.\"\r\n",
       "}\r\n"
@@ -156,6 +158,7 @@
      "output_type": "stream",
      "text": [
       "{\r\n",
+      "    \"_type\": \"prompt\",\r\n",
       "    \"input_variables\": [\"adjective\", \"content\"],\r\n",
       "    \"template_path\": \"simple_template.txt\"\r\n",
       "}\r\n"
@@ -279,6 +282,7 @@
       "prefix: \r\n",
       "    Write antonyms for the following words.\r\n",
       "example_prompt:\r\n",
+      "    _type: prompt\r\n",
       "    input_variables:\r\n",
       "        [\"input\", \"output\"]\r\n",
       "    template:\r\n",
@@ -346,6 +350,7 @@
       "prefix: \r\n",
       "    Write antonyms for the following words.\r\n",
       "example_prompt:\r\n",
+      "    _type: prompt\r\n",
       "    input_variables:\r\n",
       "        [\"input\", \"output\"]\r\n",
       "    template:\r\n",
@@ -413,6 +418,7 @@
       "    \"input_variables\": [\"adjective\"],\r\n",
       "    \"prefix\": \"Write antonyms for the following words.\",\r\n",
       "    \"example_prompt\": {\r\n",
+      "        \"_type\": \"prompt\",\r\n",
       "        \"input_variables\": [\"input\", \"output\"],\r\n",
       "        \"template\": \"Input: {input}\\nOutput: {output}\"\r\n",
       "    },\r\n",
@@ -478,6 +484,7 @@
       "    \"input_variables\": [\"adjective\"],\r\n",
       "    \"prefix\": \"Write antonyms for the following words.\",\r\n",
       "    \"example_prompt\": {\r\n",
+      "        \"_type\": \"prompt\",\r\n",
       "        \"input_variables\": [\"input\", \"output\"],\r\n",
       "        \"template\": \"Input: {input}\\nOutput: {output}\"\r\n",
       "    },\r\n",
@@ -542,6 +549,7 @@
      "output_type": "stream",
      "text": [
       "{\r\n",
+      "    \"_type\": \"prompt\",\r\n",
       "    \"input_variables\": [\"input\", \"output\"],\r\n",
       "    \"template\": \"Input: {input}\\nOutput: {output}\" \r\n",
       "}\r\n"
@@ -622,7 +630,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.9"
+   "version": "3.11.2"
   },
   "vscode": {
    "interpreter": {

docs/modules/prompts/examples/simple_prompt.json

@@ -1,4 +1,5 @@
 {
+    "_type": "prompt",
     "input_variables": ["adjective", "content"],
     "template": "Tell me a {adjective} joke about {content}."
 }

docs/modules/prompts/examples/simple_prompt.yaml

@@ -1,3 +1,4 @@
+_type: prompt
 input_variables:
     ["adjective", "content"]
 template: 

docs/modules/prompts/examples/simple_prompt_with_template_file.json

@@ -1,4 +1,5 @@
 {
+    "_type": "prompt",
     "input_variables": ["adjective", "content"],
     "template_path": "simple_template.txt"
 }