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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 get_related_fields(model_class, field_name, path=""):
 """ Get fields for a given model """

    if field_name:
        field, model, direct, m2m = _get_field_by_name(model_class, field_name)
        if direct:
            # Direct field
            try:
                new_model = _get_remote_field(field).parent_model()
            except AttributeError:
                new_model = _get_remote_field(field).model
        else:
            # Indirect related field
            if hasattr(field, 'related_model'):  # Django>=1.8
                new_model = field.related_model
            else:
                new_model = field.model()

        path += field_name
        path += '__'
    else:
        new_model = model_class

    new_fields = get_relation_fields_from_model(new_model)
    model_ct = ContentType.objects.get_for_model(new_model)

    return (new_fields, model_ct, path)