refactor: Replace string concatenation with joins

Same as previous commits. "".join() is better that "string" + "another_string" + "another_string_2", because strings are immutable.
Also, changed for loops with list comprehension. This is much faster and would improve performance.

Signed-off-by: nothingbutlucas <69118979+nothingbutlucas@users.noreply.github.com>

RNS/Utilities/rnx.py

@@ -28,7 +28,7 @@ import argparse
 import shlex
 import time
 import sys
-import tty
+# import tty # Commented this because commented lines below use it
 import os
 
 from RNS._version import __version__
@@ -39,9 +39,10 @@ reticulum = None
 allow_all = False
 allowed_identity_hashes = []
 
+
 def prepare_identity(identity_path):
     global identity
-    if identity_path == None:
+    if identity_path is None:
         identity_path = RNS.Reticulum.identitypath+"/"+APP_NAME
 
     if os.path.isfile(identity_path):
@@ -52,6 +53,7 @@ def prepare_identity(identity_path):
         identity = RNS.Identity()
         identity.to_file(identity_path)
 
+
 def listen(configdir, identitypath = None, verbosity = 0, quietness = 0, allowed = [], print_identity = False, disable_auth = None, disable_announce=False):
     global identity, allow_all, allowed_identity_hashes, reticulum
 
@@ -69,7 +71,7 @@ def listen(configdir, identitypath = None, verbosity = 0, quietness = 0, allowed
     if disable_auth:
         allow_all = True
     else:
-        if allowed != None:
+        if allowed is not None:
             for a in allowed:
                 try:
                     dest_len = (RNS.Reticulum.TRUNCATED_HASHLENGTH//8)*2
@@ -297,6 +299,7 @@ def remote_execution_progress(request_receipt):
 link = None
 listener_destination = None
 remote_exec_grace = 2.0
+
 def execute(configdir, identitypath = None, verbosity = 0, quietness = 0, detailed = False, mirror = False, noid = False, destination = None, command = None, stdin = None, stdoutl = None, stderrl = None, timeout = RNS.Transport.PATH_REQUEST_TIMEOUT, result_timeout = None, interactive = False):
     global identity, reticulum, link, listener_destination, remote_exec_grace
 
@@ -548,7 +551,6 @@ def main():
         parser.add_argument("--stdout", action='store', default=None, help="max size in bytes of returned stdout", type=int)
         parser.add_argument("--stderr", action='store', default=None, help="max size in bytes of returned stderr", type=int)
         parser.add_argument("--version", action="version", version="rnx {version}".format(version=__version__))
-        
         args = parser.parse_args()
 
         if args.listen or args.print_identity:
@@ -668,6 +670,7 @@ def size_str(num, suffix='B'):
 
     return "%.2f%s%s" % (num, last_unit, suffix)
 
+
 def pretty_time(time, verbose=False):
     days = int(time // (24 * 3600))
     time = time % (24 * 3600)
@@ -684,31 +687,24 @@ def pretty_time(time, verbose=False):
 
     components = []
     if days > 0:
-        components.append(str(days)+" day"+sd if verbose else str(days)+"d")
+        components.append("".join([str(days), " day", sd if verbose else str(days), "d"]))
 
     if hours > 0:
-        components.append(str(hours)+" hour"+sh if verbose else str(hours)+"h")
+        components.append("".join([str(hours), " hour", sh if verbose else str(hours), "h"]))
 
     if minutes > 0:
-        components.append(str(minutes)+" minute"+sm if verbose else str(minutes)+"m")
+        components.append("".join([str(minutes), " minute", sm if verbose else str(minutes), "m"]))
 
     if seconds > 0:
-        components.append(str(seconds)+" second"+ss if verbose else str(seconds)+"s")
+        components.append("".join([str(seconds), " second", ss if verbose else str(seconds), "s"]))
 
-    i = 0
-    tstr = ""
-    for c in components:
-        i += 1
-        if i == 1:
-            pass
-        elif i < len(components):
-            tstr += ", "
-        elif i == len(components):
-            tstr += " and "
+    if len(components) > 1:
+        time_string = "".join([", ".join(components[:-1]), " and ", components[-1]])
+    else:
+        time_string = components[0] if components else ""
 
-        tstr += c
+    return time_string
 
-    return tstr
 
 if __name__ == "__main__":
     main()