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Solve TypeError: ‘dict’ object does not support indexing when running SQL queries in Python

I ran into another silly error, for which I wanted to share the solution in order to save you some time. It occurs when trying to run a query using Python’s SQLAlchemy libary. Let’s dive right in. The problem When you’re trying to run a query, either by using Pandas’… 

How to copy the first value of a group to all rows in the group of a Pandas DataFrame

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Recently, I needed to calculate the relative change of a value compared to the first value within a DataFrame group, a GroupBy object. With SQL, I would use a window function (e.g. PARTITION BY in PostgreSQL). In this article, we’ll do it in Pandas (Python). To demonstrate, let’s start with…