diff --git a/copyparty/__main__.py b/copyparty/__main__.py
index 65ec9f18..88f3fdec 100644
--- a/copyparty/__main__.py
+++ b/copyparty/__main__.py
@@ -32,7 +32,7 @@ try:
 except:
     HAVE_SSL = False
 
-printed = ""
+printed = []
 
 
 class RiceFormatter(argparse.HelpFormatter):
@@ -65,10 +65,8 @@ class Dodge11874(RiceFormatter):
 
 
 def lprint(*a, **ka):
-    global printed
-
     txt = " ".join(unicode(x) for x in a) + ka.get("end", "\n")
-    printed += txt
+    printed.append(txt)
     if not VT100:
         txt = ansi_re.sub("", txt)
 
@@ -722,7 +720,7 @@ def main(argv=None):
 
     # signal.signal(signal.SIGINT, sighandler)
 
-    SvcHub(al, argv, printed).run()
+    SvcHub(al, argv, "".join(printed)).run()
 
 
 if __name__ == "__main__":
diff --git a/copyparty/tcpsrv.py b/copyparty/tcpsrv.py
index 29d23759..7d2cb3e4 100644
--- a/copyparty/tcpsrv.py
+++ b/copyparty/tcpsrv.py
@@ -160,15 +160,15 @@ class TcpSrv(object):
                 continue
 
             if ln == ln.lstrip():
-                dev = re.split(r'[: ]', ln)[0]
+                dev = re.split(r"[: ]", ln)[0]
 
-            if "UP" in re.split(r'[<>, \t]', ln):
+            if "UP" in re.split(r"[<>, \t]", ln):
                 up = True
-            
-            m = re.match(r'^\s+inet\s+([^ ]+)', ln)
+
+            m = re.match(r"^\s+inet\s+([^ ]+)", ln)
             if m:
                 ip = m.group(1)
-        
+
         return eps
 
     def ips_linux(self):
diff --git a/copyparty/th_srv.py b/copyparty/th_srv.py
index 8264514f..dc3965c7 100644
--- a/copyparty/th_srv.py
+++ b/copyparty/th_srv.py
@@ -9,7 +9,6 @@ import hashlib
 import threading
 import subprocess as sp
 
-from .__init__ import PY2, unicode
 from .util import fsenc, vsplit, statdir, runcmd, Queue, Cooldown, BytesIO, min_ex
 from .bos import bos
 from .mtag import HAVE_FFMPEG, HAVE_FFPROBE, ffprobe
@@ -39,7 +38,7 @@ try:
         pass
 
     try:
-        import pillow_avif
+        import pillow_avif  # noqa: F401  # pylint: disable=unused-import
 
         HAVE_AVIF = True
     except:
@@ -398,7 +397,7 @@ class ThumbSrv(object):
 
     def _run_ff(self, cmd):
         # self.log((b" ".join(cmd)).decode("utf-8"))
-        ret, sout, serr = runcmd(cmd, timeout=self.args.th_convt)
+        ret, _, serr = runcmd(cmd, timeout=self.args.th_convt)
         if not ret:
             return
 
@@ -583,7 +582,7 @@ class ThumbSrv(object):
                 if age > maxage:
                     with self.mutex:
                         safe = True
-                        for k in self.busy.keys():
+                        for k in self.busy:
                             if k.lower().replace("\\", "/").startswith(cmp):
                                 safe = False
                                 break
diff --git a/copyparty/u2idx.py b/copyparty/u2idx.py
index 89400133..073ed3d1 100644
--- a/copyparty/u2idx.py
+++ b/copyparty/u2idx.py
@@ -38,6 +38,8 @@ class U2idx(object):
             self.log("your python does not have sqlite3; searching will be disabled")
             return
 
+        self.active_id = None
+        self.active_cur = None
         self.cur = {}
         self.mem_cur = sqlite3.connect(":memory:")
         self.mem_cur.execute(r"create table a (b text)")
diff --git a/copyparty/up2k.py b/copyparty/up2k.py
index 4f064437..3f4e02e4 100644
--- a/copyparty/up2k.py
+++ b/copyparty/up2k.py
@@ -22,7 +22,6 @@ from .util import (
     Queue,
     ProgressPrinter,
     SYMTIME,
-    fsdec,
     fsenc,
     absreal,
     sanitize_fn,
@@ -948,7 +947,7 @@ class Up2k(object):
                     in_progress.pop(w)
                     n_done += 1
 
-                for w in to_delete.keys():
+                for w in to_delete:
                     q = "delete from mt where w = ? and +k = 't:mtp'"
                     cur.execute(q, (w,))
 
diff --git a/copyparty/util.py b/copyparty/util.py
index 2fe5ec32..e41bce83 100644
--- a/copyparty/util.py
+++ b/copyparty/util.py
@@ -21,16 +21,16 @@ import subprocess as sp  # nosec
 from datetime import datetime
 from collections import Counter
 
-from .__init__ import PY2, WINDOWS, ANYWIN, VT100, unicode
+from .__init__ import PY2, WINDOWS, ANYWIN, VT100
 from .stolen import surrogateescape
 
 FAKE_MP = False
 
 try:
     if FAKE_MP:
-        import multiprocessing.dummy as mp  # noqa: F401
+        import multiprocessing.dummy as mp  # noqa: F401  # pylint: disable=unused-import
     else:
-        import multiprocessing as mp  # noqa: F401
+        import multiprocessing as mp  # noqa: F401  # pylint: disable=unused-import
 except ImportError:
     # support jython
     mp = None
@@ -38,13 +38,13 @@ except ImportError:
 if not PY2:
     from urllib.parse import unquote_to_bytes as unquote
     from urllib.parse import quote_from_bytes as quote
-    from queue import Queue
-    from io import BytesIO
+    from queue import Queue  # pylint: disable=unused-import
+    from io import BytesIO  # pylint: disable=unused-import
 else:
     from urllib import unquote  # pylint: disable=no-name-in-module
     from urllib import quote  # pylint: disable=no-name-in-module
     from Queue import Queue  # pylint: disable=import-error,no-name-in-module
-    from StringIO import StringIO as BytesIO
+    from StringIO import StringIO as BytesIO  # pylint: disable=unused-import
 
 
 try:
@@ -114,16 +114,22 @@ MIMES = {
     "m4a": "audio/mp4",
     "jpg": "image/jpeg",
 }
-for ln in """text css html csv
+
+
+def _add_mimes():
+    for ln in """text css html csv
 application json wasm xml pdf rtf zip
 image webp jpeg png gif bmp
 audio aac ogg wav
 video webm mp4 mpeg
 font woff woff2 otf ttf
 """.splitlines():
-    k, vs = ln.split(" ", 1)
-    for v in vs.strip().split():
-        MIMES[v] = "{}/{}".format(k, v)
+        k, vs = ln.split(" ", 1)
+        for v in vs.strip().split():
+            MIMES[v] = "{}/{}".format(k, v)
+
+
+_add_mimes()
 
 
 REKOBO_KEY = {
@@ -175,8 +181,8 @@ class Cooldown(object):
             now = time.time()
 
             ret = False
-            v = self.hist.get(key, 0)
-            if now - v > self.maxage:
+            pv = self.hist.get(key, 0)
+            if now - pv > self.maxage:
                 self.hist[key] = now
                 ret = True
 
@@ -395,7 +401,7 @@ def nuprint(msg):
 def rice_tid():
     tid = threading.current_thread().ident
     c = sunpack(b"B" * 5, spack(b">Q", tid)[-5:])
-    return "".join("\033[1;37;48;5;{}m{:02x}".format(x, x) for x in c) + "\033[0m"
+    return "".join("\033[1;37;48;5;{0}m{0:02x}".format(x) for x in c) + "\033[0m"
 
 
 def trace(*args, **kwargs):
@@ -616,6 +622,9 @@ class MultipartParser(object):
             r'^content-disposition:(?: *|.*; *)filename="(.*)"', re.IGNORECASE
         )
 
+        self.boundary = None
+        self.gen = None
+
     def _read_header(self):
         """
         returns [fieldname, filename] after eating a block of multipart headers
@@ -1101,17 +1110,17 @@ def s3enc(mem_cur, rd, fn):
             ret.append(v)
         except:
             ret.append("//" + w8b64enc(v))
-            # self.log("mojien/{} [{}] {}".format(k, v, ret[-1][2:]))
+            # self.log("mojien [{}] {}".format(v, ret[-1][2:]))
 
     return tuple(ret)
 
 
 def s3dec(rd, fn):
     ret = []
-    for k, v in [["d", rd], ["f", fn]]:
+    for v in [rd, fn]:
         if v.startswith("//"):
             ret.append(w8b64dec(v[2:]))
-            # self.log("mojide/{} [{}] {}".format(k, ret[-1], v[2:]))
+            # self.log("mojide [{}] {}".format(ret[-1], v[2:]))
         else:
             ret.append(v)