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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_thread_block_dimensions(params, block_size_names=None):
 """thread block size from tuning params, currently using convention"""

    if not block_size_names:
        block_size_names = default_block_size_names

    block_size_x = params.get(block_size_names[0], 256)
    block_size_y = params.get(block_size_names[1], 1)
    block_size_z = params.get(block_size_names[2], 1)
    return (int(block_size_x), int(block_size_y), int(block_size_z))