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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_feature_type(feature_column):
 """ For a given feature, determine if it is real, binary or constant. Here binary means that only two unique values occur in the feature. :param feature_column: The feature column :type feature_column: pandas.Series :return: 'constant', 'binary' or 'real' """

    n_unique_values = len(set(feature_column.values))
    if n_unique_values == 1:
        _logger.warning("[test_feature_significance] Feature {} is constant".format(feature_column.name))
        return 'constant'
    elif n_unique_values == 2:
        return 'binary'
    else:
        return 'real'