I have created two Discord Bots that are currently available on the biggest Discord Bot website on the internet: Top.gg
Both bots are built on the Discord.py API Wrapper.

The first bot was created as a joke at first to make fun of one of my friends who always corrects our grammatical mistakes. It is quite simple, as it was the first one I created. It mostly parses through the string returned after a message is sent and adds the correction to a separate string, which is printed out at the end.

The second bot is a real bot that I created to help people with calculus problems, and I wanted to help them where they are, mostly on Discord. The bot uses the Sympy Python module (documentation) for most of its commands, and sometimes multiple times in more complicated commands.
You are able to calculate derivatives, antiderivatives, limits, definite integrals, the area between curves, average and instantaneous rates of change, average value, volumes of revolutions, and cross-sections.
The prefix of every command is “+”, and to get every command available write “+help” to get a message in discord that lays out every command and helpful tips.

This is what “+help” will “print” out:

Limits: +lims [function],[value]
Derivative: +diff [function]
Antiderivative: +inte [function]
Definite Integral: +defi [function],[a],[b]
Area Between Curves: +area [function1],[function2],[a],[b]
Average Value: +avgv [function],[a],[b]
Instantaneous Rate of Change: +iroc [function],[value]
Average Rate of Change on (a,b): +aroc [function],[a],[b]

Volume of Revolutions:
OBS: If the function(s) is revolved around another line than the x-axis, remember to subtract that line from the [function] part. Ex. if x^2 is revolved around x=2, then you would write x**2 – 2 as the function.
Disk Volume of Revolution: +dvol [function],[a],[b]
Washer Volume of Revolution: +wvol [function1],[function2],[a],[b]

Cross Section Volumes:
OBS: These calculations can take a couple of seconds.
Cross Section of Square: +cssq [function1],[function2],[a],[b]
Cross Section of Semi-Circle: +cssc [function1],[function2],[a],[b]

How functions and symbols look:
2x^2 = 2x*2
e^x = exp(x)
Squareroot of x = sqrt(x)
Infinity = oo

Helpful tip: All these functions are default for “y=” or “f(x)” but if you need horizontal strips for areas or your volume is revolved the y-axis then write the function as a “x=” or “f(y)” and also find the y= values for the limits, then you can put then in just using x, and get your answer!!!