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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load_map_file(filename, name=None, check_integrity=True):
 """ Loads a ContainerMap configuration from a YAML file. :param filename: YAML file name. :type filename: unicode | str :param name: Name of the ContainerMap. If ``None`` will attempt to find a ``name`` element on the root level of the document; an empty string names the map according to the file, without extension. :type name: unicode | str :param check_integrity: Performs a brief integrity check; default is ``True``. :type check_integrity: bool :return: A ContainerMap object. :rtype: ContainerMap """

    if name == '':
        base_name = os.path.basename(filename)
        map_name, __, __ = os.path.basename(base_name).rpartition(os.path.extsep)
    else:
        map_name = name
    with open(filename, 'r') as f:
        return load_map(f, name=map_name, check_integrity=check_integrity)