For detailed instructions, see https://support.bitpay.com/hc/en-us/articles/115003001203-How-do-I-configure-and-use-the-BitPay-Python-Library-
You must have BitPay or test.bitpay merchant account to use this library. Signing up for a merchant account is free. More information about setting up a test.bitpay merchant account and a testnet bitcoin wallet can be found here: https://bitpay.com/docs/testing
BitPay's python library was developed in Python 3.7. The recommended method of installion is using pip.
pip3 install 'bitpay'
The bitpay library allows authenticating with BitPay, creating invoices, and retrieving invoices.
Before pairing with BitPay.com, you'll need to log in to your BitPay account and navigate to /api-tokens. Generate a new pairing code and use it in the next step. You can try out various functions using the Python REPL. In this example, it's assumed that we are working against the bitpay test server and have generated the pairing code "abcdefg".
> from bitpay.client import Client
> client = Client(api_uri="https://test.bitpay.com") #if api_uri is not passed, it defaults to "https://bitpay.com"
> client.pair_pos_client("abcdefg")
Using the same web client from the last step:
> client.create_invoice({"price": 20, "currency": "USD", "token": client.tokens['pos']})
That will return the invoice as JSON. Other parameters can be sent, see the BitPay REST API documentation for details.