Retrieving data from an excel File through inbound Email action.

Hi Everyone,
I have been trying to retrieve the data from an Excel file into my code for some implementation using the inbound email action. So, I have got two approaches for the same, i.e.,
1. Using the import set loader 
But it is used when we want to store data into a table using any transform map, etc. But I don't want to store the data in any table. Instead, I wanted to get the data from an Excel file into my code in the form of an object, so that I can use it further for validation or any service request generation.
2. GlideExcelParser.
For this, my Instance doesn't have access to this library. So, I can't use this.

So, I want a solution using Import set only, but I'm unable to figure it out.
Can anyone please help me with that?