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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 cli(ctx, board, fpga, pack, type, size, project_dir, verbose, verbose_yosys, verbose_arachne):
 """Bitstream timing analysis."""


    # Run scons
    exit_code = SCons(project_dir).time({
        'board': board,
        'fpga': fpga,
        'size': size,
        'type': type,
        'pack': pack,
        'verbose': {
            'all': verbose,
            'yosys': verbose_yosys,
            'arachne': verbose_arachne
        }
    })
    ctx.exit(exit_code)