i2c bus error when using rpi

[gub3005]

When I run the code on my rpi, I get these errors with the ADS1115 library:
Traceback (most recent call last):
File "/home/user/water.py", line 5, in
adc = Adafruit_ADS1x15.ADS1115()
File "/usr/local/lib/python3.9/dist-packages/Adafruit_ADS1x15/ADS1x15.py", line 319, in init
super(ADS1115, self).init(*args, **kwargs)
File "/usr/local/lib/python3.9/dist-packages/Adafruit_ADS1x15/ADS1x15.py", line 82, in init
self._device = i2c.get_i2c_device(address, **kwargs)
File "/usr/local/lib/python3.9/dist-packages/Adafruit_GPIO/I2C.py", line 63, in get_i2c_device
busnum = get_default_bus()
File "/usr/local/lib/python3.9/dist-packages/Adafruit_GPIO/I2C.py", line 55, in get_default_bus
raise RuntimeError('Could not determine default I2C bus for platform.')
RuntimeError: Could not determine default I2C bus for platform.