To collapse multiple columns in Pandas, follow these steps:
Step # 1: Download NumPy and Pandas.
Step # 2: Generate some random data and use it to create a Pandas dataframe.
Step # 3: Convert multiple lists into one data frame by creating a dictionary for each named list.
Step # 4: Then use the Pandas info frame in the dict. The data frame with data columns and a column for names is ready.
Step # 5: Specify which columns should be collapsed. This can be done by specifying the mapping as a dictionary, where the keys are the names of the columns to be concatenated or collapsed, and the values — the names of the resulting column.