git-p4: remove string type aliasing

Now that python2.7 is the minimum required version and we no longer use
the basestring type, it is not necessary to use type aliasing to ensure
python3 compatibility.

Signed-off-by: Yang Zhao <yang.zhao@skyboxlabs.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4.py

@@ -26,22 +26,6 @@
 import ctypes
 import errno
 
-# support basestring in python3
-try:
-    unicode = unicode
-except NameError:
-    # 'unicode' is undefined, must be Python 3
-    str = str
-    unicode = str
-    bytes = bytes
-    basestring = (str,bytes)
-else:
-    # 'unicode' exists, must be Python 2
-    str = str
-    unicode = unicode
-    bytes = str
-    basestring = basestring
-
 verbose = False
 
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