Plaid API Python

I am trying to use plaid-python to load the transaction data for customers. However I am lost with the documentation. I have initiated as per the documentation.

    configuration = plaid.Configuration(
        host=plaid.Environment.Sandbox,
        api_key={
            'clientId': PLAID_CLIENT_ID,
            'secret': PLAID_SECRET,
        })
api_client = plaid.ApiClient(configuration)
client = plaid_api.PlaidApi(api_client)

However I am lost here, with the public and access tokens. Can someone help me generate the public and access tokens.

Thanks