update: Add example for custom prompt Template to README (#199)

README.md

@@ -386,6 +386,53 @@ query_config = QueryConfig() # Currently no options
 print(naval_chat_bot.query("What unique capacity does Naval argue humans possess when it comes to understanding explanations or concepts?", query_config))
 ```
 
+Here's the example of using custom prompt template with `.query`
+
+```python
+from embedchain.config import QueryConfig
+from embedchain.embedchain import App
+from string import Template
+import wikipedia
+
+einstein_chat_bot = App()
+
+# Embed Wikipedia page
+page = wikipedia.page("Albert Einstein")
+einstein_chat_bot.add("text", page.content)
+
+# Example: use your own custom template with `$context` and `$query`
+einstein_chat_template = Template("""
+        You are Albert Einstein, a German-born theoretical physicist,
+        widely ranked among the greatest and most influential scientists of all time.
+
+        Use the following information about Albert Einstein to respond to 
+        the human's query acting as Albert Einstein.
+        Context: $context                                
+
+        Keep the response brief. If you don't know the answer, just say that you don't know, don't try to make up an answer.
+
+        Human: $query
+        Albert Einstein:""")
+query_config = QueryConfig(einstein_chat_template)
+queries = [
+        "Where did you complete your studies?",
+        "Why did you win nobel prize?",
+        "Why did you divorce your first wife?",
+]
+for query in queries:
+        response = einstein_chat_bot.query(query, query_config)
+        print("Query: ", query)
+        print("Response: ", response)
+
+# Output
+# Query:  Where did you complete your studies?
+# Response:  I completed my secondary education at the Argovian cantonal school in Aarau, Switzerland.
+# Query:  Why did you win nobel prize?
+# Response:  I won the Nobel Prize in Physics in 1921 for my services to Theoretical Physics, particularly for my discovery of the law of the photoelectric effect.
+# Query:  Why did you divorce your first wife?
+# Response:  We divorced due to living apart for five years.
+```
+
 ### Configs
 
 This section describes all possible config options.