Instruction: Describe a method for merging two DataFrames where the key for merging is based on overlapping date ranges.
Context: This question tests the candidate's ability to solve complex data merging scenarios, a common challenge in time series and financial data analysis.
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Firstly, to clarify our objective: when we talk about merging two DataFrames based on overlapping date ranges, we're addressing a scenario where the merge key isn't a direct match but rather a condition where the date ranges in one DataFrame fall within those of another. This is a common issue in time series analysis, financial data, and anywhere data is aggregated over periods.
The approach I recommend involves a combination of pandas functionalities and custom logic. The steps are as follows:...