How can I install an old PyQT version (version 4)

Question

I'm trying to use the repository at ttps://bitbucket.org/jpcgt/flatcam, which requires PyQT4 and Python3.

Unfortunately trying to install pyqt4 does not work, since my anaconda distribution does not include any pre-5 versions:

(base) $ conda search pyqt
Loading channels: done
# Name                       Version           Build  Channel             
pyqt                           5.6.0  py27h22d08a2_6  pkgs/main           
pyqt                           5.6.0  py27h4b1e83c_5  pkgs/main           
pyqt                           5.6.0  py35h0e41ada_5  pkgs/main           
pyqt                           5.6.0  py35h22d08a2_6  pkgs/main           
pyqt                           5.6.0  py36h0386399_5  pkgs/main           
pyqt                           5.6.0  py36h22d08a2_6  pkgs/main           
pyqt                           5.6.0  py37h22d08a2_6  pkgs/main           
pyqt                           5.9.2  py27h05f1152_2  pkgs/main           
pyqt                           5.9.2  py27h22d08a2_0  pkgs/main           
pyqt                           5.9.2  py27h22d08a2_1  pkgs/main           
pyqt                           5.9.2  py27h751905a_0  pkgs/main           
pyqt                           5.9.2  py35h05f1152_2  pkgs/main           
pyqt                           5.9.2  py35h22d08a2_1  pkgs/main           
pyqt                           5.9.2  py35h751905a_0  pkgs/main           
pyqt                           5.9.2  py36h05f1152_2  pkgs/main           
pyqt                           5.9.2  py36h22d08a2_0  pkgs/main           
pyqt                           5.9.2  py36h22d08a2_1  pkgs/main           
pyqt                           5.9.2  py36h751905a_0  pkgs/main           
pyqt                           5.9.2  py37h05f1152_2  pkgs/main           
pyqt                           5.9.2  py37h22d08a2_0  pkgs/main           
pyqt                           5.9.2  py37h22d08a2_1  pkgs/main           
pyqt                           5.9.2  py38h05f1152_4  pkgs/main 

Clearly it was possible to install this at some point, and still should be to support code that has not upgraded to PyQT5. Any idea how I can achieve this in anaconda?

Answer 1

Use the free channel, which contains many old package versions. From the docs :

The free channel contains packages created prior to September 26, 2017. Prior to conda 4.7, the free channel was part of the defaults channel.

conda search -c free pyqt
Loading channels: done
# Name                       Version           Build  Channel
pyqt                          4.10.4          py26_0  free
pyqt                          4.10.4          py26_1  free
pyqt                          4.10.4          py27_0  free
pyqt                          4.10.4          py27_1  free
pyqt                          4.10.4          py33_0  free
pyqt                          4.10.4          py33_1  free
pyqt                          4.10.4          py34_0  free
pyqt                          4.10.4          py34_1  free
pyqt                          4.11.4          py27_0  free
pyqt                          4.11.4          py27_2  free
pyqt                          4.11.4          py27_3  free
pyqt                          4.11.4          py27_4  free
pyqt                          4.11.4          py27_5  free
pyqt                          4.11.4          py27_6  free
pyqt                          4.11.4          py27_7  free
pyqt                          4.11.4          py34_2  free
pyqt                          4.11.4          py34_3  free
pyqt                          4.11.4          py34_4  free
pyqt                          4.11.4          py34_5  free
pyqt                          4.11.4          py34_6  free
pyqt                          4.11.4          py34_7  free
pyqt                          4.11.4          py35_0  free
pyqt                          4.11.4          py35_2  free
pyqt                          4.11.4          py35_3  free
pyqt                          4.11.4          py35_4  free
pyqt                          4.11.4          py35_5  free
pyqt                          4.11.4          py35_6  free
pyqt                          4.11.4          py35_7  free
pyqt                           5.6.0          py27_0  free
pyqt                           5.6.0          py27_1  free
pyqt                           5.6.0          py27_2  free
pyqt                           5.6.0  py27h224ed30_5  pkgs/main
pyqt                           5.6.0  py27h6e61f57_6  pkgs/main
pyqt                           5.6.0          py34_0  free
pyqt                           5.6.0          py34_1  free
pyqt                           5.6.0          py34_2  free
pyqt                           5.6.0          py35_0  free
pyqt                           5.6.0          py35_1  free
pyqt                           5.6.0          py35_2  free
pyqt                           5.6.0  py35ha878b3d_6  pkgs/main
pyqt                           5.6.0  py35hd46907b_5  pkgs/main
pyqt                           5.6.0          py36_2  free
pyqt                           5.6.0  py36ha878b3d_6  pkgs/main
pyqt                           5.6.0  py36hb5ed885_5  pkgs/main
pyqt                           5.6.0  py37ha878b3d_6  pkgs/main
pyqt                           5.9.2  py35h1aa27d4_0  pkgs/main
pyqt                           5.9.2  py35h6538335_2  pkgs/main
pyqt                           5.9.2  py35ha878b3d_0  pkgs/main
pyqt                           5.9.2  py36h1aa27d4_0  pkgs/main
pyqt                           5.9.2  py36h6538335_2  pkgs/main
pyqt                           5.9.2  py36ha878b3d_0  pkgs/main
pyqt                           5.9.2  py37h6538335_2  pkgs/main
pyqt                           5.9.2  py37ha878b3d_0  pkgs/main
pyqt                           5.9.2  py38ha925a31_4  pkgs/main