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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 solve(ctx, length, height, silent, profile, **pieces):
 """ Solve a puzzle constrained by board dimensions and pieces. """

    # Check that at least one piece is provided.
    if not sum(pieces.values()):
        context = click.get_current_context()
        raise BadParameter('No piece provided.', ctx=context, param_hint=[
            '--{}'.format(label) for label in PIECE_LABELS])

    # Setup the optionnal profiler.
    profiler = BProfile('solver-profile.png', enabled=profile)

    solver = SolverContext(length, height, **pieces)
    logger.info(repr(solver))

    logger.info('Searching positions...')
    with profiler:
        start = time.time()
        for result in solver.solve():
            if not silent:
                click.echo(u'{}'.format(result))
        processing_time = time.time() - start

    logger.info('{} results found in {:.2f} seconds.'.format(
        solver.result_counter, processing_time))

    if profile:
        logger.info('Execution profile saved at {}'.format(
            profiler.output_path))