tox update and linter fixes

- F841 local variable ... is assigned to but never used
- F812 list comprehension redefines ...

Also added pyleveldb recipe to list of broken recipes, the error was:
```
/home/user/.local/share/python-for-android/build/other_builds/hostpython2/desktop/hostpython2/Include/Python.h:47:19:
fatal error: crypt.h: No such file or directory
```
See https://api.travis-ci.org/v3/job/488398065/log.txt

Author: AndreMiras

ci/constants.py

@@ -39,6 +39,8 @@ class TargetPython(Enum):
     'protobuf_cpp',
     'xeddsa',
     'x3dh',
+    # fatal error: crypt.h: No such file or directory
+    'pyleveldb',
     'pynacl',
     'doubleratchet',
     'omemo',
@@ -77,6 +79,8 @@ class TargetPython(Enum):
     # requires `libpq-dev` system dependency e.g. for `pg_config` binary
     'psycopg2',
     'netifaces',
+    # fatal error: crypt.h: No such file or directory
+    'pyleveldb',
     'protobuf_cpp',
     # most likely some setup in the Docker container, because it works in host
     'pyjnius', 'pyopenal',

ci/rebuild_updated_recipes.py

@@ -63,15 +63,12 @@ def build(target_python, requirements):
     requirements = ','.join(requirements)
     logger.info('requirements: {}'.format(requirements))
     with current_directory('testapps/'):
-        try:
-            # iterates to stream the output
-            for line in sh.python(
-                    testapp, 'apk', '--sdk-dir', android_sdk_home,
-                    '--ndk-dir', android_ndk_home, '--bootstrap', 'sdl2', '--requirements',
-                    requirements, _err_to_out=True, _iter=True):
-                print(line)
-        except sh.ErrorReturnCode as e:
-            raise
+        # iterates to stream the output
+        for line in sh.python(
+                testapp, 'apk', '--sdk-dir', android_sdk_home,
+                '--ndk-dir', android_ndk_home, '--bootstrap', 'sdl2', '--requirements',
+                requirements, _err_to_out=True, _iter=True):
+            print(line)
 
 
 def main():

pythonforandroid/bootstraps/common/build/build.py

@@ -426,7 +426,7 @@ def make_package(args):
         target = fileh.read().strip()
     android_api = target.split('-')[1]
     try:
-        android_api_int_test = int(android_api)
+        int(android_api)
     except (ValueError, TypeError):
         raise ValueError(
             "failed to extract the Android API level from " +

pythonforandroid/bootstraps/pygame/build/buildlib/argparse.py

@@ -1468,7 +1468,7 @@ def _check_conflict(self, action):
     def _handle_conflict_error(self, action, conflicting_actions):
         message = _('conflicting option string(s): %s')
         conflict_string = ', '.join([option_string
-                                     for option_string, action
+                                     for option_string, action  # noqa F812
                                      in conflicting_actions])
         raise ArgumentError(action, message % conflict_string)
 
@@ -2071,7 +2071,7 @@ def _parse_optional(self, arg_string):
         # if multiple actions match, the option string was ambiguous
         if len(option_tuples) > 1:
             options = ', '.join(
-                    [option_string for action, option_string, explicit_arg in option_tuples])
+                    [option_string for action, option_string, explicit_arg in option_tuples])  # noqa F812
             tup = arg_string, options
             self.error(_('ambiguous option: %s could match %s') % tup)
 

pythonforandroid/bootstraps/sdl2/__init__.py

@@ -14,8 +14,6 @@ def run_distribute(self):
         info_main("# Creating Android project ({})".format(self.name))
 
         arch = self.ctx.archs[0]
-        python_install_dir = self.ctx.get_python_install_dir()
-        from_crystax = self.ctx.python_recipe.from_crystax
 
         if len(self.ctx.archs) > 1:
             raise ValueError("SDL2/gradle support only one arch")

pythonforandroid/build.py

@@ -528,7 +528,6 @@ def not_has_package(self, name, arch=None):
 
 def build_recipes(build_order, python_modules, ctx):
     # Put recipes in correct build order
-    bs = ctx.bootstrap
     info_notify("Recipe build order is {}".format(build_order))
     if python_modules:
         python_modules = sorted(set(python_modules))

pythonforandroid/distribution.py

@@ -79,8 +79,6 @@ def get_distribution(cls, ctx, name=None, recipes=[],
 
         existing_dists = Distribution.get_distributions(ctx)
 
-        needs_build = True  # whether the dist needs building, will be returned
-
         possible_dists = existing_dists
 
         name_match_dist = None

pythonforandroid/python.py

@@ -421,7 +421,7 @@ def build_arch(self, arch):
                 shprint(sh.cp, join('Modules', 'Setup.dist'),
                         join(build_dir, 'Modules', 'Setup'))
 
-                result = shprint(sh.make, '-j', str(cpu_count()), '-C', build_dir)
+                shprint(sh.make, '-j', str(cpu_count()), '-C', build_dir)
         else:
             info('Skipping {name} ({version}) build, as it has already '
                  'been completed'.format(name=self.name, version=self.version))

pythonforandroid/recipes/pygame/__init__.py

@@ -68,7 +68,6 @@ def build_arch(self, arch):
             shprint(sh.find, build_lib[0], '-name', '*.o', '-exec',
                     env['STRIP'], '{}', ';')
 
-        python_install_path = join(self.ctx.build_dir, 'python-install')
         warning('Should remove pygame tests etc. here, but skipping for now')
 
 

pythonforandroid/recipes/pyleveldb/__init__.py

@@ -12,7 +12,6 @@ class PyLevelDBRecipe(CompiledComponentsPythonRecipe):
     site_packages_name = 'leveldb'
 
     def build_arch(self, arch):
-        env = self.get_recipe_env(arch)
         with current_directory(self.get_build_dir(arch.arch)):
             # Remove source in this pypi package
             sh.rm('-rf', 'leveldb', 'leveldb.egg-info', 'snappy')