DEP: remove the support for Python 3.5 and 3.6

Author: dragonyanglong

Diff for: .travis.yml

@@ -7,8 +7,6 @@ os:
 
 env:
   - MYUSEMC=true MYPYTHON_VERSION=2.7
-  - MYUSEMC=true MYPYTHON_VERSION=3.5
-  - MYUSEMC=true MYPYTHON_VERSION=3.6
   - MYUSEMC=true MYPYTHON_VERSION=3.7
   - MYUSEMC=true MYPYTHON_VERSION=3.8
   - MYUSEMC=true MYPYTHON_VERSION=3.9

Diff for: CHANGELOG.md

@@ -12,6 +12,8 @@
 
 ### Removed
 
+- Remove the support for Python 3.5, 3.6.
+
 ### Fixed
 
 ## Version 3.0.2 - 2022-10-12

Diff for: README.rst

@@ -27,7 +27,7 @@ user manual at http://diffpy.github.io/diffpy.structure.
 REQUIREMENTS
 ------------------------------------------------------------------------
 
-The diffpy.structure package requires Python 3.5 or later or 2.7 and
+The diffpy.structure package requires Python 3.7 or later or 2.7 and
 the following software:
 
 * ``setuptools`` - software distribution tools for Python

Diff for: setup.py

@@ -12,7 +12,7 @@
 
 # Use this version when git data are not available, like in git zip archive.
 # Update when tagging a new release.
-FALLBACK_VERSION = '3.0.1.post0'
+FALLBACK_VERSION = '3.1.0'
 
 # determine if we run with Python 3.
 PY3 = (sys.version_info[0] == 3)
@@ -116,8 +116,6 @@ def getversioncfg():
         'Operating System :: POSIX',
         'Operating System :: Unix',
         'Programming Language :: Python :: 2.7',
-        'Programming Language :: Python :: 3.5',
-        'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',