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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 example_bigbeds():
 """ Returns list of example bigBed files """

    hits = []
    d = data_dir()
    for fn in os.listdir(d):
        fn = os.path.join(d, fn)
        if os.path.splitext(fn)[-1] == '.bigBed':
            hits.append(os.path.abspath(fn))
    return hits