def get_index_of_feature(feature_list, item):
    """
    Gets the index of the feature in the provided feature list

    :rtype : int
    :param feature_list: List of features to search from
    :param item: The feature to search
    :return: The index where the feature was founded, -1 otherwise
    """

    # getting the indexes where 'item' occurs
    idxs = [k for k in range(len(feature_list)) if feature_list[k][0] == item]

    # counting the indexes
    idxs_count = len(idxs)

    # if the feature appears more than one time
    if idxs_count > 1:
        raise Exception("""
        There was a problem in the feature extraction process.\r\n
        The feature is counted more than one time.""")

    # the index if any, -1 if the feature doesn't appear
    return idxs[0] if idxs_count == 1 else -1