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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 _initialize_indices(model_class, name, bases, attrs):
 """Stores the list of indexed attributes."""

    model_class._indices = []
    for k, v in attrs.iteritems():
        if isinstance(v, (Attribute, ListField)) and v.indexed:
            model_class._indices.append(k)
    if model_class._meta['indices']:
        model_class._indices.extend(model_class._meta['indices'])