# Defining a function in Pandas [closed]

Hello Data Scientists,

Disclaimer: I am a Beginner learning Python and at the same time just trying out a lot of things.

I am doing some data extraction on a file with with weekly deaths in Switzerland between the years of 2010 - 2019 (to be found at https://opendata.swiss/en/). I narrowed down the age group of 0-64, now I am separating this group into deaths per year.

I find it cumbersome to repeat assigning the variable to an operator. I wondered if there would be any way to define a function and input a list. Maybe it would be even nicer to have some operation extract the years from the file itself and work it out automatically.

Here is my state of knowledge:

I tried to follow a template and as you can see I get a lot of error messages. Probably I am doing it all wrong?

Please let me know if you have any suggestions and how solve it and thank you very much for taking the time to ponder my question! :)

If you want to get the total number of deaths for each year in the data there is a much easier way than manually going through all the years and subsetting and summing the data. pandas has the groupby and agg methods for this:
file.groupby("KJ").agg({"Anzahl_Todesfalle": "sum"})

This line of code makes groups in the dataset based on the KJ column, and within those groups aggregates the Anzahl_Todesfalle column by summing all the values, returning one row for each year containing the total number of deaths.