'Remote file whether exists'

def remote_file_exists(self, dst, file_system='flash:'):

    full_path = (file_system + dst)
    file_name = os.path.basename(full_path)
    file_path = os.path.dirname(full_path)
    file_path = (file_path + '/')
    xml_str = (CE_NC_GET_FILE_INFO % (file_name, file_path))
    ret_xml = get_nc_config(self.module, xml_str)
    if ('<data/>' in ret_xml):
        return (False, 0)
    xml_str = ret_xml.replace('\r', '').replace('\n', '').replace('xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"', '').replace('xmlns="http://www.huawei.com/netconf/vrp"', '')
    root = ElementTree.fromstring(xml_str)
    topo = root.find('data/vfm/dirs/dir')
    if (topo is None):
        return (False, 0)
    for eles in topo:
        if (eles.tag in ['DirSize']):
            return (True, int(eles.text.replace(',', '')))
    return (False, 0)
