Reducing size of pyinstaller exe

I have a simple pandas pyinstaller exe which is over 40MB.

My exe example:

import collections
import csv
import selenium
import pandas

print('hi')

40MB+ for this seems a bit overkill.

How can I reduce this as much as possible?

One method:

pyinstaller --onefile --exclude matplotlib --exclude scipy --exclude pandas --exclude numpy.py

This however is not practical considering how big the exclusion list would be.

How do I select a folder for pyinstaller to get modules from and exclude everything else so I may have a small application?

Spec file:

a = Analysis(['123.py'],
             pathex=['C:\\Users\\AA\\ZZ'],
             binaries=[],
             datas=[],
             hiddenimports=[],
             hookspath=[],
             runtime_hooks=[],
             excludes=[],
             win_no_prefer_redirects=False,
             win_private_assemblies=False,
             cipher=block_cipher)
pyz = PYZ(a.pure, a.zipped_data,
             cipher=block_cipher)
exe = EXE(pyz,
          a.scripts,
          a.binaries,
          a.zipfiles,
          a.datas,
          name='123',
          debug=False,
          strip=False,
          upx=True,
          runtime_tmpdir=None,
          console=True )

It's also worth mentioning. By default, Pyinstaller does not detect pandas.

Add:

hiddenimports = ['pandas._libs.tslibs.timedeltas']

To: C:\Users\<NAME>\AppData\Local\Programs\Python\Python36\Lib\site-packages\PyInstaller\hooks

A possible solution when using multiple executables, could be to link each executable to a separate folder or executable with all imports.

try setting up your environment with a virtualenv, and install in there only the required libraries

some details on working with virtual env are here: https://virtualenv.pypa.io/en/stable/