diff --git a/tools/Android.bp b/tools/Android.bp
index 59831a6..243cb56 100644
--- a/tools/Android.bp
+++ b/tools/Android.bp
@@ -123,3 +123,11 @@
         "merge-event-log-tags.py",
     ],
 }
+
+python_binary_host {
+    name: "java-event-log-tags",
+    srcs: [
+        "event_log_tags.py",
+        "java-event-log-tags.py",
+    ],
+}
diff --git a/tools/event_log_tags.py b/tools/event_log_tags.py
index a6ae9f1..e859b6b 100644
--- a/tools/event_log_tags.py
+++ b/tools/event_log_tags.py
@@ -14,21 +14,21 @@
 
 """A module for reading and parsing event-log-tags files."""
 
+import dataclasses
 import re
 import sys
+from typing import Optional
 
-class Tag(object):
-  __slots__ = ["tagnum", "tagname", "description", "filename", "linenum"]
-
-  def __init__(self, tagnum, tagname, description, filename, linenum):
-    self.tagnum = tagnum
-    self.tagname = tagname
-    self.description = description
-    self.filename = filename
-    self.linenum = linenum
+@dataclasses.dataclass
+class Tag:
+  tagnum: int
+  tagname: str
+  description: Optional[str]
+  filename: str
+  linenum: int
 
 
-class TagFile(object):
+class TagFile:
   """Read an input event-log-tags file."""
   def AddError(self, msg, linenum=None):
     if linenum is None:
@@ -76,14 +76,11 @@
           self.options[parts[1]] = parts[2:]
           continue
 
-        if parts[0] == "?":
-          tag = None
-        else:
-          try:
-            tag = int(parts[0])
-          except ValueError:
-            self.AddError("\"%s\" isn't an integer tag or '?'" % (parts[0],))
-            continue
+        try:
+          tag = int(parts[0])
+        except ValueError:
+          self.AddError("\"%s\" isn't an integer tag" % (parts[0],))
+          continue
 
         tagname = parts[1]
         if len(parts) == 3:
@@ -128,8 +125,8 @@
       out = sys.stdout
       output_file = "<stdout>"
     else:
-      out = open(output_file, "wb")
-    out.write(str.encode(data))
+      out = open(output_file, "w")
+    out.write(data)
     out.close()
   except (IOError, OSError) as e:
     print("failed to write %s: %s" % (output_file, e), file=sys.stderr)
diff --git a/tools/java-event-log-tags.py b/tools/java-event-log-tags.py
index bbd65fa..e3dc07e 100755
--- a/tools/java-event-log-tags.py
+++ b/tools/java-event-log-tags.py
@@ -15,16 +15,12 @@
 # limitations under the License.
 
 """
-Usage: java-event-log-tags.py [-o output_file] <input_file> <merged_tags_file>
-
 Generate a java class containing constants for each of the event log
 tags in the given input file.
-
--h to display this usage message and exit.
 """
 
 from io import StringIO
-import getopt
+import argparse
 import os
 import os.path
 import re
@@ -32,57 +28,14 @@
 
 import event_log_tags
 
-output_file = None
+parser = argparse.ArgumentParser(description=__doc__)
+parser.add_argument('-o', dest='output_file')
+parser.add_argument('file')
+args = parser.parse_args()
 
-try:
-  opts, args = getopt.getopt(sys.argv[1:], "ho:")
-except getopt.GetoptError as err:
-  print(str(err))
-  print(__doc__)
-  sys.exit(2)
-
-for o, a in opts:
-  if o == "-h":
-    print(__doc__)
-    sys.exit(2)
-  elif o == "-o":
-    output_file = a
-  else:
-    print("unhandled option %s" % (o,), file=sys.stderr)
-    sys.exit(1)
-
-if len(args) != 1 and len(args) != 2:
-  print("need one or two input files, not %d" % (len(args),))
-  print(__doc__)
-  sys.exit(1)
-
-fn = args[0]
+fn = args.file
 tagfile = event_log_tags.TagFile(fn)
 
-if len(args) > 1:
-  # Load the merged tag file (which should have numbers assigned for all
-  # tags.  Use the numbers from the merged file to fill in any missing
-  # numbers from the input file.
-  merged_fn = args[1]
-  merged_tagfile = event_log_tags.TagFile(merged_fn)
-  merged_by_name = dict([(t.tagname, t) for t in merged_tagfile.tags])
-  for t in tagfile.tags:
-    if t.tagnum is None:
-      if t.tagname in merged_by_name:
-        t.tagnum = merged_by_name[t.tagname].tagnum
-      else:
-        # We're building something that's not being included in the
-        # product, so its tags don't appear in the merged file.  Assign
-        # them all an arbitrary number so we can emit the java and
-        # compile the (unused) package.
-        t.tagnum = 999999
-else:
-  # Not using the merged tag file, so all tags must have manually assigned
-  # numbers
-  for t in tagfile.tags:
-    if t.tagnum is None:
-      tagfilef.AddError("tag \"%s\" has no number" % (tagname,), tag.linenum)
-
 if "java_package" not in tagfile.options:
   tagfile.AddError("java_package option not specified", linenum=0)
 
@@ -141,11 +94,11 @@
 for t in tagfile.tags:
   methodName = javaName("write_" + t.tagname)
   if t.description:
-    args = [arg.strip("() ").split("|") for arg in t.description.split(",")]
+    fn_args = [arg.strip("() ").split("|") for arg in t.description.split(",")]
   else:
-    args = []
-  argTypesNames = ", ".join([javaTypes[int(arg[1])] + " " + javaName(arg[0]) for arg in args])
-  argNames = "".join([", " + javaName(arg[0]) for arg in args])
+    fn_args = []
+  argTypesNames = ", ".join([javaTypes[int(arg[1])] + " " + javaName(arg[0]) for arg in fn_args])
+  argNames = "".join([", " + javaName(arg[0]) for arg in fn_args])
   buffer.write("\n  public static void %s(%s) {" % (methodName, argTypesNames))
   buffer.write("\n    android.util.EventLog.writeEvent(%s%s);" % (t.tagname.upper(), argNames))
   buffer.write("\n  }\n")
@@ -153,8 +106,8 @@
 
 buffer.write("}\n");
 
-output_dir = os.path.dirname(output_file)
+output_dir = os.path.dirname(args.output_file)
 if not os.path.exists(output_dir):
   os.makedirs(output_dir)
 
-event_log_tags.WriteOutput(output_file, buffer)
+event_log_tags.WriteOutput(args.output_file, buffer)
diff --git a/tools/merge-event-log-tags.py b/tools/merge-event-log-tags.py
index 292604c..5730c11 100755
--- a/tools/merge-event-log-tags.py
+++ b/tools/merge-event-log-tags.py
@@ -15,22 +15,13 @@
 # limitations under the License.
 
 """
-Usage: merge-event-log-tags.py [-o output_file] [input_files...]
-
 Merge together zero or more event-logs-tags files to produce a single
 output file, stripped of comments.  Checks that no tag numbers conflict
 and fails if they do.
-
--h to display this usage message and exit.
 """
 
 from io import StringIO
-import getopt
-try:
-  import hashlib
-except ImportError:
-  import md5 as hashlib
-import struct
+import argparse
 import sys
 
 import event_log_tags
@@ -38,32 +29,10 @@
 errors = []
 warnings = []
 
-output_file = None
-pre_merged_file = None
-
-# Tags with a tag number of ? are assigned a tag in the range
-# [ASSIGN_START, ASSIGN_LIMIT).
-ASSIGN_START = 900000
-ASSIGN_LIMIT = 1000000
-
-try:
-  opts, args = getopt.getopt(sys.argv[1:], "ho:m:")
-except getopt.GetoptError as err:
-  print(str(err))
-  print(__doc__)
-  sys.exit(2)
-
-for o, a in opts:
-  if o == "-h":
-    print(__doc__)
-    sys.exit(2)
-  elif o == "-o":
-    output_file = a
-  elif o == "-m":
-    pre_merged_file = a
-  else:
-    print("unhandled option %s" % (o,), file=sys.stderr)
-    sys.exit(1)
+parser = argparse.ArgumentParser(description=__doc__)
+parser.add_argument('-o', dest='output_file')
+parser.add_argument('files', nargs='*')
+args = parser.parse_args()
 
 # Restrictions on tags:
 #
@@ -77,12 +46,7 @@
 by_tagname = {}
 by_tagnum = {}
 
-pre_merged_tags = {}
-if pre_merged_file:
-  for t in event_log_tags.TagFile(pre_merged_file).tags:
-    pre_merged_tags[t.tagname] = t
-
-for fn in args:
+for fn in args.files:
   tagfile = event_log_tags.TagFile(fn)
 
   for t in tagfile.tags:
@@ -93,12 +57,6 @@
     if t.tagname in by_tagname:
       orig = by_tagname[t.tagname]
 
-      # Allow an explicit tag number to define an implicit tag number
-      if orig.tagnum is None:
-        orig.tagnum = t.tagnum
-      elif t.tagnum is None:
-        t.tagnum = orig.tagnum
-
       if (t.tagnum == orig.tagnum and
           t.description == orig.description):
         # if the name and description are identical, issue a warning
@@ -114,7 +72,7 @@
             linenum=t.linenum)
       continue
 
-    if t.tagnum is not None and t.tagnum in by_tagnum:
+    if t.tagnum in by_tagnum:
       orig = by_tagnum[t.tagnum]
 
       if t.tagname != orig.tagname:
@@ -125,8 +83,7 @@
         continue
 
     by_tagname[t.tagname] = t
-    if t.tagnum is not None:
-      by_tagnum[t.tagnum] = t
+    by_tagnum[t.tagnum] = t
 
   errors.extend(tagfile.errors)
   warnings.extend(tagfile.warnings)
@@ -140,38 +97,6 @@
   for fn, ln, msg in warnings:
     print("%s:%d: warning: %s" % (fn, ln, msg), file=sys.stderr)
 
-# Python's hash function (a) isn't great and (b) varies between
-# versions of python.  Using md5 is overkill here but is the same from
-# platform to platform and speed shouldn't matter in practice.
-def hashname(str):
-  d = hashlib.md5(str).digest()[:4]
-  return struct.unpack("!I", d)[0]
-
-# Assign a tag number to all the entries that say they want one
-# assigned.  We do this based on a hash of the tag name so that the
-# numbers should stay relatively stable as tags are added.
-
-# If we were provided pre-merged tags (w/ the -m option), then don't
-# ever try to allocate one, just fail if we don't have a number
-
-for name, t in sorted(by_tagname.items()):
-  if t.tagnum is None:
-    if pre_merged_tags:
-      try:
-        t.tagnum = pre_merged_tags[t.tagname]
-      except KeyError:
-        print("Error: Tag number not defined for tag `%s'. Have you done a full build?" % t.tagname,
-              file=sys.stderr)
-        sys.exit(1)
-    else:
-      while True:
-        x = (hashname(name) % (ASSIGN_LIMIT - ASSIGN_START - 1)) + ASSIGN_START
-        if x not in by_tagnum:
-          t.tagnum = x
-          by_tagnum[x] = t
-          break
-        name = "_" + name
-
 # by_tagnum should be complete now; we've assigned numbers to all tags.
 
 buffer = StringIO()
@@ -181,4 +106,4 @@
   else:
     buffer.write("%d %s\n" % (t.tagnum, t.tagname))
 
-event_log_tags.WriteOutput(output_file, buffer)
+event_log_tags.WriteOutput(args.output_file, buffer)