In Pandas, groupby() is a function that allows us to group data based on one or more variables, and then apply various functions to the groups. It returns a DataFrameGroupBy object that can be used to perform further analysis on the grouped data.

We use groupby() in Pandas to perform split-apply-combine operations on the data, which involves:

Splitting the data into groups based on one or more variables.

Applying a function or set of functions to each group.

Combining the results into a new DataFrame.

Inorder to get a particular group from a groupby DataFrame by key in Pandas, you can use various methods, two of them are given below:

1. Using the "get_group()" method:

The simplest way to get a particular group from a groupby DataFrame by key is to use the `get_group()` method of the groupby object. This method returns a DataFrame containing all rows of the specified group.

Example:

2. Using the "filter()" method:

Another way to get a particular group from a groupby DataFrame by key is to use the `filter()` method of the groupby object. This method filters the groups based on a condition and returns a DataFrame containing all rows of the selected groups. You can define a custom function that selects the group with the desired key, and then apply this function to the groupby object using `filter()` .