Access private key after personal.newAccount in web3.py

Question

I have created an Ethereum account using web3.py in python 3.6:

web3.personal.newAccount('password')

How do I access the private key for that account?

Answer 1

When you create an account on your node (which w3.personal.newAccount() does), the node hosts the private key; direct access to it is not intended.

If you must have local access to the private key, you can either:

• Generate a new one with w3.eth.account.create(extra_entropy)
• Extract the existing key from your node's keyfile.

If the node is geth, extracting the key looks like:

with open('~/.ethereum/keystore/UTC--...4909639D2D17A3F753ce7d93fa0b9aB12E') as keyfile:
    encrypted_key = keyfile.read()
    private_key = w3.eth.account.decrypt(encrypted_key, 'correcthorsebatterystaple')

Security tip -- Do not save the key or password anywhere, especially into a shared source file