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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 optional_install():
 """Generates configuration settings for optional functionality of ISAMBARD."""

    # reduce
    print('{BOLD}Setting up Reduce (optional){END_C}'.format(**text_colours))
    reduce = {}
    reduce_path = get_user_path('Please provide a path to your reduce executable.', required=False)
    reduce['path'] = str(reduce_path)
    reduce['folder'] = str(reduce_path.parent) if reduce_path else ''
    settings['reduce'] = reduce

    # naccess
    print('{BOLD}Setting up naccess (optional){END_C}'.format(**text_colours))
    naccess = {}
    naccess_path = get_user_path('Please provide a path to your naccess executable.', required=False)
    naccess['path'] = str(naccess_path)
    settings['naccess'] = naccess

    # profit
    print('{BOLD}Setting up ProFit (optional){END_C}'.format(**text_colours))
    profit = {}
    profit_path = get_user_path('Please provide a path to your ProFit executable.', required=False)
    profit['path'] = str(profit_path)
    settings['profit'] = profit
    return