Attaches HTTP Basic Authentication to the given Request object.
    Arguments should be considered non-positional.

def http_basic(r, username, password):
    """Attaches HTTP Basic Authentication to the given Request object.
    Arguments should be considered non-positional.

    """
    username = str(username)
    password = str(password)

    auth_s = b64encode('%s:%s' % (username, password))
    r.headers['Authorization'] = ('Basic %s' % auth_s)

    return r