import base64


def make_headers(username, password):
    """Add standard headers - Basic Authorization and JSON content type. Pass auth string as decoded base64."""
    cred_str = '{}:{}'.format(username, password).encode('utf-8')
    creds = base64.b64encode(cred_str).decode('utf-8')
    headers = {'Content-Type': 'application/json',
               'Authorization': 'Basic {}'.format(creds)}
    return headers