BashChain #

This notebook showcases using LLMs and a bash process to perform simple filesystem commands.

from langchain.chains import LLMBashChain
from langchain.llms import OpenAI

llm = OpenAI(temperature=0)

text = "Please write a bash script that prints 'Hello World' to the console."

bash_chain = LLMBashChain.from_llm(llm, verbose=True)

bash_chain.run(text)

> Entering new LLMBashChain chain...
Please write a bash script that prints 'Hello World' to the console.

```bash
echo "Hello World"

Code: ['echo "Hello World"'] Answer: Hello World

Finished chain.

'Hello World\n'

 Customize Prompt
 [#](#customize-prompt "Permalink to this headline")
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 You can also customize the prompt that is used. Here is an example prompting to avoid using the ‘echo’ utility
 

from langchain.prompts.prompt import PromptTemplate from langchain.chains.llm_bash.prompt import BashOutputParser

_PROMPT_TEMPLATE = """If someone asks you to perform a task, your job is to come up with a series of bash commands that will perform the task. There is no need to put "#!/bin/bash" in your answer. Make sure to reason step by step, using this format: Question: "copy the files in the directory named 'target' into a new directory at the same level as target called 'myNewDirectory'" I need to take the following actions:

• List all files in the directory
• Create a new directory
• Copy the files from the first directory into the second directory

ls
mkdir myNewDirectory
cp -r target/\* myNewDirectory

Do not use 'echo' when writing the script.

That is the format. Begin! Question: {question}"""

PROMPT = PromptTemplate(input_variables=["question"], template=_PROMPT_TEMPLATE, output_parser=BashOutputParser())

bash_chain = LLMBashChain.from_llm(llm, prompt=PROMPT, verbose=True)

text = "Please write a bash script that prints 'Hello World' to the console."

bash_chain.run(text)

Entering new LLMBashChain chain... Please write a bash script that prints 'Hello World' to the console.

printf "Hello World\n"

Code: ['printf "Hello World\n"'] Answer: Hello World

Finished chain.

'Hello World\n'

 Persistent Terminal
 [#](#persistent-terminal "Permalink to this headline")
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 By default, the chain will run in a separate subprocess each time it is called. This behavior can be changed by instantiating with a persistent bash process.
 

from langchain.utilities.bash import BashProcess

persistent_process = BashProcess(persistent=True) bash_chain = LLMBashChain.from_llm(llm, bash_process=persistent_process, verbose=True)

text = "List the current directory then move up a level."

bash_chain.run(text)

Entering new LLMBashChain chain... List the current directory then move up a level.

ls
cd ..

Code: ['ls', 'cd ..'] Answer: api.ipynb llm_summarization_checker.ipynb constitutional_chain.ipynb moderation.ipynb llm_bash.ipynb openai_openapi.yaml llm_checker.ipynb openapi.ipynb llm_math.ipynb pal.ipynb llm_requests.ipynb sqlite.ipynb

Finished chain.

'api.ipynb\t\t\tllm_summarization_checker.ipynb\r\nconstitutional_chain.ipynb\tmoderation.ipynb\r\nllm_bash.ipynb\t\t\topenai_openapi.yaml\r\nllm_checker.ipynb\t\topenapi.ipynb\r\nllm_math.ipynb\t\t\tpal.ipynb\r\nllm_requests.ipynb\t\tsqlite.ipynb'

Run the same command again and see that the state is maintained between calls

bash_chain.run(text)

Entering new LLMBashChain chain... List the current directory then move up a level.

ls
cd ..

Code: ['ls', 'cd ..'] Answer: examples getting_started.ipynb index_examples generic how_to_guides.rst

Finished chain.

'examples\t\tgetting_started.ipynb\tindex_examples\r\ngeneric\t\t\thow_to_guides.rst'