Requirement of pull-up or pull-down resistors

According to the blog, the circuit diagram shows the resistors for a float switch/sensor. However we are not using any float switch, as we want to do a simplified version of the experiment where we just automate the pH monitoring of the water

We are confused as to how to use the pull-up or pull-down resistors for the pH sensor and the pump? I read that each of the SDA and SCL pin of the pump need to be connected to a pull-up resistor (preferably 4.7k Ohms). We are using Atlas Scientific pH sensor kit and Atlas Scientific Peristaltic Pump. Both are connected in I2C format with a raspberry pi. Thanks a lot,

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Raspberry Pis have integrated pull-up resistors on both SDA and SCL, so additional resistors are not needed.