Partialing Prompt Templates¶
Cassandra-powered prompt templates support partialing. Building on the previous examples:
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                from langchain.prompts import createCassandraPromptTemplate
from langchain.prompts import createCassandraPromptTemplate
        
        In [2]:
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                from cqlsession import getCQLSession, getCQLKeyspace
cqlMode = 'astra_db' # 'astra_db'/'local'
session = getCQLSession(mode=cqlMode)
keyspace = getCQLKeyspace(mode=cqlMode)
from cqlsession import getCQLSession, getCQLKeyspace
cqlMode = 'astra_db' # 'astra_db'/'local'
session = getCQLSession(mode=cqlMode)
keyspace = getCQLKeyspace(mode=cqlMode)
        
        In [3]:
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                ctemplate0 = """Please answer a question from a user.
Keep in mind that the user's age is {user_age} and they live in a city with
nickname {city_nickname}.
USER'S QUESTION: {user_question}
YOUR ANSWER:
"""
cassPrompt = createCassandraPromptTemplate(
    session=session,
    keyspace=keyspace,
    template=ctemplate0,
    input_variables=['city', 'name', 'user_question'],
    field_mapper={
        'user_age': ('people', 'age'),
        'city_nickname': ('nickname_by_city', 'nickname'),
    },
)
ctemplate0 = """Please answer a question from a user.
Keep in mind that the user's age is {user_age} and they live in a city with
nickname {city_nickname}.
USER'S QUESTION: {user_question}
YOUR ANSWER:
"""
cassPrompt = createCassandraPromptTemplate(
    session=session,
    keyspace=keyspace,
    template=ctemplate0,
    input_variables=['city', 'name', 'user_question'],
    field_mapper={
        'user_age': ('people', 'age'),
        'city_nickname': ('nickname_by_city', 'nickname'),
    },
)
        
        Creating a Partial Prompt¶
Let us "partial" the prompt above, specifying the DB-lookup inputs and leaving only the user question unspecified:
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                cassPartialPrompt = cassPrompt.partial(city='lisbon', name='Pedro')
cassPartialPrompt = cassPrompt.partial(city='lisbon', name='Pedro')
        
        When rendering the template, the full lookup takes place at once:
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                print(cassPartialPrompt.format(user_question='Em verdade, o que quiseres?'))
print(cassPartialPrompt.format(user_question='Em verdade, o que quiseres?'))
        
        Please answer a question from a user. Keep in mind that the user's age is 1 and they live in a city with nickname ACidade. USER'S QUESTION: Em verdade, o que quiseres? YOUR ANSWER:
Partialing and Chat Prompt Templates¶
Unfortunately, this is not supported at the LangChain level. Let's create a two-item chat sequence,
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                systemTemplate = """
You are a chat assistant, helping a user of age {user_age} from a city
they refer to as {city_nickname}.
"""
cassSystemPrompt = createCassandraPromptTemplate(
    session=session,
    keyspace=keyspace,
    template=systemTemplate,
    input_variables=['city', 'name'],
    field_mapper={
        'user_age': ('people', 'age'),
        'city_nickname': ('nickname_by_city', 'nickname'),
    },
)
from langchain.prompts import (
    ChatPromptTemplate,
    SystemMessagePromptTemplate,
    HumanMessagePromptTemplate,
)
systemMessagePrompt = SystemMessagePromptTemplate(prompt=cassSystemPrompt)
humanTemplate = "{text}"
humanMessagePrompt = HumanMessagePromptTemplate.from_template(humanTemplate)
cassChatPrompt = ChatPromptTemplate.from_messages(
    [systemMessagePrompt, humanMessagePrompt]
)
systemTemplate = """
You are a chat assistant, helping a user of age {user_age} from a city
they refer to as {city_nickname}.
"""
cassSystemPrompt = createCassandraPromptTemplate(
    session=session,
    keyspace=keyspace,
    template=systemTemplate,
    input_variables=['city', 'name'],
    field_mapper={
        'user_age': ('people', 'age'),
        'city_nickname': ('nickname_by_city', 'nickname'),
    },
)
from langchain.prompts import (
    ChatPromptTemplate,
    SystemMessagePromptTemplate,
    HumanMessagePromptTemplate,
)
systemMessagePrompt = SystemMessagePromptTemplate(prompt=cassSystemPrompt)
humanTemplate = "{text}"
humanMessagePrompt = HumanMessagePromptTemplate.from_template(humanTemplate)
cassChatPrompt = ChatPromptTemplate.from_messages(
    [systemMessagePrompt, humanMessagePrompt]
)
        
        and try to "partial" it by specifying the DB-lookup parameters:
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                try:
    cassChatPartialPrompt = cassChatPrompt.partial(
        city='turin',
        name='beppe'
    )
except NotImplementedError:
    print('"NotImplementedError" raised by partialing ChatPromptTemplate')
try:
    cassChatPartialPrompt = cassChatPrompt.partial(
        city='turin',
        name='beppe'
    )
except NotImplementedError:
    print('"NotImplementedError" raised by partialing ChatPromptTemplate')
        
        "NotImplementedError" raised by partialing ChatPromptTemplate