- use python built in methods

- eliminate the usage of wget for manual install for systems that doesn't have wget preinstalled.
- works with Python 2 and 3

download-xflux.py

@@ -1,5 +1,11 @@
-from sys import maxsize
-import os
+from sys import maxsize, version_info
+
+if version_info[0] == 3:
+    from urllib.request import urlretrieve
+else:
+    from urllib import urlretrieve
+
+import tarfile
 
 # There is similar code in ./debian/postinst. If you are changing this
 # you probably want to change that too.
@@ -12,8 +18,17 @@ def download_xflux():
         print("Downloading 64-bit xflux ...")
         url = "https://justgetflux.com/linux/xflux64.tgz"
     tarchive = "/tmp/xflux.tgz"
-    os.system("wget '%s' -O'%s'" % (url, tarchive))
-    os.system("tar -xvf '%s'" % tarchive)
+
+    # use python's builtins methods to eliminate external program
+    # dependencies for manual install
+    # in case internet connection isn't available to download wget
+    # & not every linux system (minimal) has wget (nor curl) preinstalled.
+    urlretrieve(url, tarchive)
+
+    print("Extracting {} ...".format(tarchive))
+    tar = tarfile.open(tarchive)
+    tar.extractall()
+    tar.close()
 
 if __name__ == '__main__':
     download_xflux()