Cognitive Class Labs is a very flexible environment. It allows users to install just about any package or library with the exception of those that require native operating system code installation (we do not provide root authority for obvious security reasons). Most users do not have problems installing python packages they need, however, from time to time people do run in to problems. Most of the time, these issues are caused by improper installation command or using the wrong repository.
For data centric libraries we strongly recommend using conda install. For example, to install the latest version of the xlrd package to read contents of Microsoft Excel files, use the following command in your notebook:
!conda install -c anaconda xlrd --yes