Which packages are installed? - python-3.x

Question

I'm new to Python.
I'm using winpython3 and winspyder3. How can I check which packages, modules and plugins are installed?
I didn't find anything here.
Thanks for the answers... but....
#Vineeth Sai: I'm using winspyder3, I get these error:
Start of code
pip freeze
The following command must be run outside of the IPython shell:
$ pip freeze
The Python package manager (pip) can only be used from outside of IPython.
Please reissue the `pip` command in a separate terminal or command prompt.
See the Python documentation for more information on how to install packages:
https://docs.python.org/3/installing/
End of Code
# Rajeev Atmakuri:
With the Code of your link, I get following output:
Start of code:
runfile('D:/Python/packages_001.py', wdir='D:/Python')
Traceback (most recent call last):
File "<ipython-input-6-a7b650970979>", line 1, in <module>
runfile('D:/Python/packages_001.py', wdir='D:/Python')
File "C:\WPy-3662\python-3.6.6.amd64\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 668, in runfile
execfile(filename, namespace)
File "C:\WPy-3662\python-3.6.6.amd64\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 108, in execfile
exec(compile(f.read(), filename, 'exec'), namespace)
File "D:/Python/packages_001.py", line 9, in <module>
installed_packages = pip.get_installed_distributions()
AttributeError: module 'pip' has no attribute 'get_installed_distributions'
End of code
at all:
if you know octave: with
start of code:
pkg list
end of code
you get a complete list of the installed packages...