'Prepare HTTP request and call _connect'

def _send_cmd(self, method, url, params=None):

    params = (params or {})
    if (method in ('GET', 'PUT')):
        if params:
            url += ('?' + self._param_string(params))
        body = ''
    elif (method == 'POST'):
        body = self._param_string(params)
    else:
        body = ''
    return self._connect(method, url, body)
