drop pyversion & is_python3 checking

We're committed to Python 3 at this point, so purge all the
is_python3 related dynamic checks.

Bug: https://crbug.com/gerrit/10418
Change-Id: I4c8b405d6de359b8b83223c9f4b9c8ffa18ea1a2
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/292383
Reviewed-by: Chris Mcdonald <cjmcdonald@google.com>
Tested-by: Mike Frysinger <vapier@google.com>

project.py

@@ -25,6 +25,7 @@ import sys
 import tarfile
 import tempfile
 import time
+import urllib.parse
 
 from color import Coloring
 from git_command import GitCommand, git_require
@@ -39,16 +40,6 @@ from repo_trace import IsTrace, Trace
 
 from git_refs import GitRefs, HEAD, R_HEADS, R_TAGS, R_PUB, R_M, R_WORKTREE_M
 
-from pyversion import is_python3
-if is_python3():
-  import urllib.parse
-else:
-  import imp
-  import urlparse
-  urllib = imp.new_module('urllib')
-  urllib.parse = urlparse
-  input = raw_input  # noqa: F821
-
 
 # Maximum sleep time allowed during retries.
 MAXIMUM_RETRY_SLEEP_SEC = 3600.0