- some updates in the requirements file and in setup_ubuntu.sh; for now versions higher than 5.12.1 of pyqt5 are not working

requirements.txt

@@ -1,7 +1,8 @@
 # This file contains python only requirements to be installed with pip
 # Python packages that cannot be installed with pip (e.g. PyQt5, GDAL) are not included.
 # Usage: pip3 install -r requirements.txt
-numpy >=1.16
+pyqt5==5.12
+numpy>=1.16
 matplotlib>=3.1
 cycler>=0.10
 python-dateutil>=2.1

setup_ubuntu.sh

@@ -3,6 +3,7 @@ sudo apt install --reinstall libpng-dev libfreetype6 libfreetype6-dev libgeos-de
 sudo apt install --reinstall python3-dev python3-pyqt5 python3-pyqt5.qtopengl python3-gdal python3-simplejson
 sudo apt install --reinstall python3-pip python3-tk python3-imaging
 
+sudo python3 -m pip install --upgrade pyqt5==5.12
 sudo python3 -m pip install --upgrade pip numpy scipy shapely rtree tk lxml cycler python-dateutil kiwisolver dill
 sudo python3 -m pip install --upgrade vispy pyopengl setuptools svg.path ortools freetype-py fontTools rasterio ezdxf
 sudo python3 -m pip install --upgrade matplotlib qrcode reportlab svglib