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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 compress(data, compresslevel=9):
 """Compress data in one shot and return the compressed string. Optional argument is the compression level, in range of 0-9. """

    buf = io.BytesIO()
    with GzipFile(fileobj=buf, mode='wb', compresslevel=compresslevel) as f:
        f.write(data)
    return buf.getvalue()