def classifyData(classifier, testdata, classMap):
    """
    Classifies data based on the previously trained model.

    Args:
        classifier: A classifier object that has been trained on the test corpus.
        testdata: A dataset to classify based on reads.
        classMap: A dictionary mapping class names to their class id used by scikit-learn.
    Returns:
        result: Test data as classified by the model.
    """
    testdata.sort()
    X = []
    for item in testdata:
        X.append(item[1:])
    Y = classifier.predict(X)
    contigIDs = list(zip(*testdata))[0]
    result = list(zip(contigIDs, Y))
    return result
