'PowerDNS Driver defaulting to using PowerDNS 3.x API (ie
"experimental").
:param    key: API key or username to used (required)
:type     key: ``str``
:param    secure: Whether to use HTTPS or HTTP. Note: Off by default
for PowerDNS.
:type     secure: ``bool``
:param    host: Hostname used for connections.
:type     host: ``str``
:param    port: Port used for connections.
:type     port: ``int``
:param    api_version: Specifies the API version to use.
``experimental`` and ``v1`` are the only valid
options. Defaults to using ``experimental``
(optional)
:type     api_version: ``str``
:return: ``None``'

def __init__(self, key, secret=None, secure=False, host=None, port=None, api_version='experimental', **kwargs):

    self.ex_server = 'localhost'
    if (api_version == 'experimental'):
        self.api_root = ''
    elif (api_version == 'v1'):
        self.api_root = '/api/v1'
    else:
        raise NotImplementedError(('Unsupported    API    version:    %s' % api_version))
    super(PowerDNSDriver, self).__init__(key=key, secure=secure, host=host, port=port, **kwargs)
