<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def list_azure_containers(config_fpath):
 """List the azure storage containers in the config file. :param config_fpath: path to the dtool config file :returns: the list of azure storage container names """

    config_content = _get_config_dict_from_file(config_fpath)
    az_container_names = []
    for key in config_content.keys():
        if key.startswith(AZURE_KEY_PREFIX):
            name = key[len(AZURE_KEY_PREFIX):]
            az_container_names.append(name)
    return sorted(az_container_names)