build: drop python<3.5 compatibility in CI and markers

.travis.yml

@@ -21,6 +21,7 @@ env:
 python:
     - "3.5"
     - "3.6"
+    - "3.7"
 
 install:
     # Optimisation: build requirements as wheels, which get cached by Travis
@@ -38,7 +39,7 @@ before_script:
 
 script:
     - python setup.py install
-    - if [ $TRAVIS_PYTHON_VERSION == 3.6 ]; then make stylecheck; fi
+    - if [ $TRAVIS_PYTHON_VERSION != 3.5 ]; then make stylecheck; fi
     - tox
 
 notifications:

requirements.txt

@@ -5,4 +5,3 @@ click>=6.2
 pyblake2>=0.9.3
 libusb1>=1.6.4
 construct>=2.9
-typing>=3.0.0; python_version < '3.5'

setup.py

@@ -130,11 +130,10 @@ setup(
     scripts=["trezorctl"],
     install_requires=install_requires,
     extras_require={
-        ':python_version < "3.5"': ["typing>=3.0.0"],
         "hidapi": ["hidapi>=0.7.99.post20"],
         "ethereum": ["rlp>=0.4.4", "ethjsonrpc>=0.3.0"],
     },
-    python_requires=">=3.3",
+    python_requires=">=3.5",
     include_package_data=True,
     zip_safe=False,
     classifiers=[

tox.ini

@@ -1,9 +1,8 @@
 [tox]
 envlist =
-    py33,
-    py34,
     py35,
     py36,
+    py37,
 
 [testenv]
 deps =