Drop support for EOL Python 3.3

conftest.py

@@ -14,7 +14,7 @@ from parso.utils import parse_version_string
 collect_ignore = ["setup.py"]
 
 VERSIONS_2 = '2.7'
-VERSIONS_3 = '3.3', '3.4', '3.5', '3.6', '3.7', '3.8'
+VERSIONS_3 = '3.4', '3.5', '3.6', '3.7', '3.8'
 
 
 @pytest.fixture(scope='session')

parso/python/issue_list.txt

@@ -172,5 +172,5 @@ A list of syntax/indentation errors I've encountered in CPython.
 Version specific:
 Python 3.5:
     'yield' inside async function
-Python 3.3/3.4:
+Python 3.4:
     can use starred expression only as assignment target

setup.py

@@ -36,7 +36,6 @@ setup(name='parso',
           'Programming Language :: Python :: 2',
           'Programming Language :: Python :: 2.7',
           'Programming Language :: Python :: 3',
-          'Programming Language :: Python :: 3.3',
           'Programming Language :: Python :: 3.4',
           'Programming Language :: Python :: 3.5',
           'Programming Language :: Python :: 3.6',

tox.ini

@@ -1,11 +1,9 @@
 [tox]
-envlist = {py27,py33,py34,py35,py36,py37}
+envlist = {py27,py34,py35,py36,py37}
 [testenv]
 extras = testing
 deps =
-    py33: pytest>=3.0.7,<3.3
     py27,py34: pytest<5
-    py33: setuptools<37
     coverage: coverage
 setenv =
 # https://github.com/tomchristie/django-rest-framework/issues/1957