I need help with a basic database

Python Help
1

Hello folks!

So I’m new here, started literally one week ago, about 2-3 hours each day
I love Python but I’m kinda stuck on something
I’m trying to create a user-friendly database about chemical elements’ isotopes, something like this:

Hydrogen = [a, b, c]
Helium = [d, e]
Carbon = [f, g, h]

Where “a”, “b” etc are floats. So far so good, not a big deal

BUT

I want something like this:

Step-1: "Please enter the result of your isotopic mass: "
Step-2: (The user gives a value, let’s say f, and it matches Carbon. However, there are more than just one - in this case, “f” - values that are true for Carbon. So, not only f, but also g and h should give away: “It’s Carbon!”) Instead, it gives me error.

My problem is that I just can’t get my code to work with a key with more than just one value

Thanks in advance!

2

Please post you code and the output when you run it.
That will allow us to help.

Put code and output in between so-called code-fences:

```
     print("like this")
```