Exception: Couldn't find a tree builder with the features you requested: lxml. Do you need to install a parser library? code example

Example 1: bs4.FeatureNotFound: Couldn't find a tree builder with the features you requested: lxml. Do you need to install a parser library?

pip install lxml

Example 2: FeatureNotFound: Couldn't find a tree builder with the features you requested: lxml. Do you need to install a parser library?

pip install lxml