Calculate Variance in Pandas DataFrame

Pandas is a Python library that is widely used to perform data analysis and machine learning tasks. It is open-source and very powerful, fast, and easy to use. Basically, while working with big data we need to analyze, manipulate and update them and the pandas' library plays a lead role there. Sometimes, we need to calculate the variance in a Pandas DataFrame. Variance is a statistical term that refers to the measurement of dispersion that calculates the spread of all data points in a data set.