DfRobot pH Sensor Raspberry with ADC ADS1115

Hello Guys,

i Try to Connect my pH Sensor on my raspPi 3B+.

So i Need to install ADS1115 driver:

i tried this on with  following link  https://wiki.dfrobot.com/Gravity__I2C_ADS1115_16-Bit_ADC_Module_Arduino_%26_Raspberry_Pi_Compatible__SKU__DFR0553

suddenly the Library/Software driver ( https://github.com/DFRobot/DFRobot_ADS1115/tree/master/RaspberryPi)  for RaspPi do not work

i tried install driver with Terminal ( as u See on the Page). 

but this failed aswell, because anything missing on the file

so i guess i need to do this Step to connect my pH Sensor to ne raspberry. 

2.: After that, How i can use my pH Sensor? 

All i found are codes for arduino

maybe u can help me.

thanks a lot and sorry for my bad english