Here is an example code that uses the pandas library to combine multiple CSV files into a single file.

The error message "ImportError: No module named" in Python usually indicates that you are trying to import a module that either does not exist or is not installed in your Python environment.

To select multiple columns in a Pandas dataframe, you can pass a list of column names to the dataframe indexing operator [].

You can get the row count of a Pandas DataFrame using the shape attribute or the len() function.

To delete a column from a Pandas DataFrame, you can use the drop() method with the axis parameter set to 1.

To rename column names in Pandas, you can use the rename method on a Pandas DataFrame object. The rename method takes a dictionary that maps old column names to new column names.

In Pandas, you can iterate over rows of a DataFrame using various methods. However, it's generally recommended to avoid using iteration as much as possible, as it can be slow and inefficient compared to vectorized operations.