Fixes #16 blocks website when app is running

app2.py

@@ -0,0 +1,63 @@
+import os
+
+# Enter the site name which you want to block
+sites_to_block = [
+    "www.facebook.com",
+    "facebook.com",
+    "www.youtube.com",
+    "youtube.com",
+    "www.gmail.com",
+    "gmail.com",
+]
+
+# different hosts for different os
+Linux_host = "/etc/hosts"
+Window_host = r"C:\Windows\System32\drivers\etc\hosts"
+default_hoster = Linux_host  # if you are on Windows, then change it to Window_host
+redirect = "127.0.0.1"
+
+if os.name == 'posix':
+    default_hoster = Linux_host
+elif os.name == 'nt':
+    default_hoster = Window_host
+else:
+    print("OS Unknown")
+    exit()
+
+
+def block_websites():
+    try:
+        print("Blocking websites...")
+        with open(default_hoster, "r+") as hostfile:
+            hosts = hostfile.read()
+            for site in sites_to_block:
+                if site not in hosts:
+                    hostfile.write(redirect + " " + site + "\n")
+        print("Websites blocked. Now stay focused!")
+    except PermissionError as e:
+        print(f"Caught a permission error: Try running as admin. {e}")
+        exit()
+
+
+def unblock_websites():
+    try:
+        print("Unblocking websites...")
+        with open(default_hoster, "r+") as hostfile:
+            hosts = hostfile.readlines()
+            hostfile.seek(0)
+            for host in hosts:
+                if not any(site in host for site in sites_to_block):
+                    hostfile.write(host)
+            hostfile.truncate()
+        print("Websites unblocked. You're free now!")
+    except PermissionError as e:
+        print(f"Caught a permission error: Try running as admin. {e}")
+        exit()
+
+
+if __name__ == "__main__":
+    try:
+        block_websites()
+        input("Press Enter to stop blocking and unblock websites...\n")
+    finally:
+        unblock_websites()