Final answer:
To check the version of an installed Python package, use the command 'pip show packagename' in the CLI or use the 'pkg_resources' module in a Python interpreter. Additionally, some packages allow you to see their version by querying 'packagename.__version__' within Python code.
Step-by-step explanation:
To check the version of an installed Python package, you can use one of several methods. One common method is to use pip, which is the package installer for Python. By running the command pip show packagename in your command line interface (CLI), pip will display a summary of information about the package, including its version number. Alternatively, if you are in a Python interpreter, you can use the pkg_resources module to check the version of an installed package with the following code:
import pkg_resources
pkg_resources.get_distribution('packagename').version
Another option, if the package follows the convention, is to query its version directly through Python code:
import packagename
print(packagename.__version__)