MAINT: Require Python>=3.8

DEPENDENCIES.md

 * caosdb-server >= 0.7.2
-* Python >= 3.6
+* Python >= 3.8
 * pip >= 20.0.2
 
 Any other dependencies are defined in the setup.py and are being installed via pip

README_SETUP.md

@@ -4,7 +4,7 @@
 
 ### Requirements ###
 
-PyCaosDB needs at least Python 3.6.  Additionally, the following packages are required (they will
+PyCaosDB needs at least Python 3.8.  Additionally, the following packages are required (they will
 typically be installed automatically):
 
 - `lxml`
@@ -19,7 +19,7 @@ Optional packages:
 
 #### Linux ####
 
-Make sure that Python (at least version 3.6) and pip is installed, using your system tools and
+Make sure that Python (at least version 3.8) and pip is installed, using your system tools and
 documentation.
 
 Then open a terminal and continue in the [Generic installation](#generic-installation) section.

setup.py

@@ -168,7 +168,7 @@ def setup_package():
             "Topic :: Scientific/Engineering :: Information Analysis",
         ],
         packages=find_packages('src'),
-        python_requires='>=3.6',
+        python_requires='>=3.8',
         package_dir={'': 'src'},
         install_requires=['lxml>=4.6.3',
                           'PyYAML>=6.0', 'future', 'PySocks>=1.6.7'],

src/caosdb/connection/connection.py

@@ -179,6 +179,8 @@ class _DefaultCaosDBServerConnection(CaosDBServerConnection):
             try:
                 ssl_version = ssl.PROTOCOL_TLS
             except AttributeError:
+                # TODO(tfitschen): This can be removed since we require Python
+                # >= 3.8 anyway, can't it?
                 # deprecated since Python 3.6, but necessary until there.
                 try:
                     ssl_version = ssl.PROTOCOL_TLSv1_2

tox.ini

 [tox]
-envlist=py36, py37, py38, py39, py310
+envlist=py38, py39, py310
 skip_missing_interpreters = true
 
 [testenv]