diff --git a/.travis.yml b/.travis.yml
index 977b0df7..eba8cca6 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -15,7 +15,7 @@ before_install:
 
 install:
 - pip3 install -r requirements.txt
-- pip3 install certifi https://github.com/bjones1/pyinstaller/archive/pyqt5_fix.zip
+- pip3 install certifi https://github.com/pyinstaller/pyinstaller/archive/develop.zip
 - npm install -g appdmg
 
 script: python3 setup.py build_binary
diff --git a/README.md b/README.md
index 85e20bf8..68c5311d 100644
--- a/README.md
+++ b/README.md
@@ -63,9 +63,9 @@ sudo pip3 install --upgrade pillow python-slugify psutil pyqt5 raven
 ## INPUT FORMATS
 **KCC** can understand and convert, at the moment, the following input types:
 - Folders containing: PNG, JPG or GIF files
-- CBZ, ZIP
-- CBR, RAR *(With `unrar` executable)*
-- CB7, 7Z *(With `7za` executable)*
+- CBZ, ZIP *(With `7z` executable)*
+- CBR, RAR *(With `7z` executable)*
+- CB7, 7Z *(With `7z` executable)*
 - PDF *(Only extracting JPG images)*
 
 ## USAGE
diff --git a/appveyor.yml b/appveyor.yml
index 2eb446ce..b603c3cc 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,11 +1,11 @@
 environment:
-  PYTHON: "C:\\Python36-x64"
+  PYTHON: "C:\\Python37-x64"
 
 install:
   - set PATH="%PYTHON%\\Scripts";"C:\\Program Files (x86)\\Inno Setup 5";%PATH%
   - "%PYTHON%\\python.exe -m pip install --upgrade pip setuptools wheel"
   - "%PYTHON%\\python.exe -m pip install -r requirements.txt"
-  - "%PYTHON%\\python.exe -m pip install certifi https://github.com/bjones1/pyinstaller/archive/pyqt5_fix.zip"
+  - "%PYTHON%\\python.exe -m pip install certifi https://github.com/pyinstaller/pyinstaller/archive/develop.zip"
   - nuget install secure-file -ExcludeVersion
   - secure-file\tools\secure-file -decrypt other\windows\sentry.py.enc -out kindlecomicconverter\sentry.py -secret %ENCRYPTION%
 
diff --git a/kindlecomicconverter/dualmetafix.py b/kindlecomicconverter/dualmetafix.py
index e6be2557..5dfb2d77 100644
--- a/kindlecomicconverter/dualmetafix.py
+++ b/kindlecomicconverter/dualmetafix.py
@@ -24,6 +24,7 @@
 class DualMetaFixException(Exception):
     pass
 
+
 # palm database offset constants
 number_of_pdb_records = 76
 first_pdb_record = 78
diff --git a/kindlecomicconverter/metadata.py b/kindlecomicconverter/metadata.py
index df87340c..62c74429 100644
--- a/kindlecomicconverter/metadata.py
+++ b/kindlecomicconverter/metadata.py
@@ -19,8 +19,6 @@
 import os
 from xml.dom.minidom import parse, Document
 from re import compile
-from subprocess import STDOUT, PIPE
-from psutil import Popen
 from tempfile import mkdtemp
 from shutil import rmtree
 from . import comicarchive
diff --git a/kindlecomicconverter/shared.py b/kindlecomicconverter/shared.py
index 32f656c3..4918a90d 100644
--- a/kindlecomicconverter/shared.py
+++ b/kindlecomicconverter/shared.py
@@ -22,8 +22,6 @@
 from hashlib import md5
 from html.parser import HTMLParser
 from distutils.version import StrictVersion
-from shutil import rmtree, copy
-from tempfile import mkdtemp
 from re import split
 from traceback import format_tb
 
@@ -49,8 +47,7 @@ def error(self, message):
 def getImageFileName(imgfile):
     name, ext = os.path.splitext(imgfile)
     ext = ext.lower()
-    if name.startswith('.') or (ext != '.png' and ext != '.jpg' and ext != '.jpeg' and ext != '.gif' and
-                                ext != '.webp'):
+    if name.startswith('.') or ext not in ['.png', '.jpg', '.jpeg', '.gif', '.webp']:
         return None
     return [name, ext]
 
@@ -88,16 +85,17 @@ def md5Checksum(fpath):
 
 def sanitizeTrace(traceback):
     return ''.join(format_tb(traceback))\
-        .replace('C:/projects/kcc/', '') \
-        .replace('c:/projects/kcc/', '') \
-        .replace('C:/python36-x64/', '')\
-        .replace('c:/python36-x64/', '')\
-        .replace('C:\\projects\\kcc\\', '') \
-        .replace('c:\\projects\\kcc\\', '') \
-        .replace('C:\\python36-x64\\', '')\
-        .replace('c:\\python36-x64\\', '')
+        .replace('C:/projects/kcc/', '')\
+        .replace('c:/projects/kcc/', '')\
+        .replace('C:/python37-x64/', '')\
+        .replace('c:/python37-x64/', '')\
+        .replace('C:\\projects\\kcc\\', '')\
+        .replace('c:\\projects\\kcc\\', '')\
+        .replace('C:\\python37-x64\\', '')\
+        .replace('c:\\python37-x64\\', '')
 
 
+# noinspection PyUnresolvedReferences
 def dependencyCheck(level):
     missing = []
     if level > 2: