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3 Extension
===================================

.. toctree::
    :maxdepth: 1

    3.1.1_counting_device
    3.1.2_welcome
    3.1.3_reversing_alarm
    3.1.4_smart_fan
    3.1.4_smart_fan_c(mcp3008)
    3.1.5_battery_indicator
    3.1.5_battery_indicator_c(mcp3008)
    3.1.6_motion_control
    3.1.7_traffic_light
    3.1.8_overheat_monitor
    3.1.8_overheat_monitor_c(mcp3008)
    3.1.9_password_lock
    3.1.10_alarm_bell
    3.1.11_morse_code_generator
    3.1.12_game_guess_number
    3.1.13_game_10_second
    3.1.14_game_not_not