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Remove pywin32 installation dependency by porting portalocker.py to ctypes.
portalocker.py lock/unlock functions now return result of operation, support for Windows 95/98/ME is removed.
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‎CHANGES.txt‎

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@@ -7,6 +7,8 @@ Entries without name were done by Richard Jones.
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Features:
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- pywin32 is not longer required to run on Windows (anatoly techtonik)
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- Rewritten portalocker.py logic in ctypes for Windows (anatoly techtonik)
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- Add an interface to register clearCache callbacks in roundupdb.
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Sometimes complicated computations may require an application cache.
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This application can now register a callback to clear the application

‎doc/installation.txt‎

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@@ -39,11 +39,6 @@ Some variants of Linux will need an additional "python dev" package
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installed for Roundup installation to work. Debian and derivatives, are
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known to require this.
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If you're on windows, you will either need to be using the ActiveState python
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distribution (at http://www.activestate.com/Products/ActivePython/), or you'll
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have to install the win32all package separately (get it from
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http://starship.python.net/crew/mhammond/win32/).
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Optional Components
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===================
@@ -83,11 +78,15 @@ pyme
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configured, you can require email to be cryptographically signed
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before roundup will allow it to make modifications to issues.
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Windows Service
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You can run Roundup as a Windows service if pywin32_ is installed.
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.. _Xapian: http://xapian.org/
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.. _pytz: http://www.python.org/pypi/pytz
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.. _Olson tz database: http://www.twinsun.com/tz/tz-link.htm
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.. _pyopenssl: http://pyopenssl.sourceforge.net
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.. _pyme: http://pyme.sourceforge.net
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.. _pywin32: http://pypi.python.org/pypi/pywin32
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Getting Roundup

‎roundup/backends/portalocker.py‎

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@@ -1,7 +1,11 @@
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#!/usr/bin/env python
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#
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# portalocker.py - Cross-platform (posix/nt) API for flock-style file locking.
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# Requires python 1.5.2 or better.
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"""Cross-platform (posix/nt) API for flock-style file locking.
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#
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# http://code.activestate.com/recipes/65203-portalocker-cross-platform-posixnt-api-for-flock-s/
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#
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"""
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Cross-platform (posix/nt) API for flock-style file locking.
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Synopsis::
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@@ -34,22 +38,69 @@
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that accompanies the win32 modules.
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:Author: Jonathan Feinberg <[email protected]>
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:Version: Id: portalocker.py,v 1.3 2001/05/29 18:47:55 Administrator Exp
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**un-cvsified by richard so the version doesn't change**
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Roundup Changes
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---------------
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2012-11-28 (anatoly techtonik)
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- Ported to ctypes
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- Dropped support for Win95, Win98 and WinME
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- Added return result
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"""
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__docformat__ = 'restructuredtext'
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import os
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if os.name == 'nt':
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import win32file
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import pywintypes
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import msvcrt
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from ctypes import *
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from ctypes.wintypes import BOOL, DWORD, HANDLE
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LOCK_SH = 0 # the default
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LOCK_NB = 0x1 # LOCKFILE_FAIL_IMMEDIATELY
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LOCK_EX = 0x2 # LOCKFILE_EXCLUSIVE_LOCK
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# is there any reason not to reuse the following structure?
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__overlapped = pywintypes.OVERLAPPED()
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# --- the code is taken from pyserial project ---
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#
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# detect size of ULONG_PTR
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def is_64bit():
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return sizeof(c_ulong) != sizeof(c_void_p)
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if is_64bit():
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ULONG_PTR = c_int64
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else:
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ULONG_PTR = c_ulong
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PVOID = c_void_p
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# --- Union inside Structure by stackoverflow:3480240 ---
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class _OFFSET(Structure):
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_fields_ = [
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('Offset', DWORD),
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('OffsetHigh', DWORD)]
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class _OFFSET_UNION(Union):
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_anonymous_ = ['_offset']
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_fields_ = [
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('_offset', _OFFSET),
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('Pointer', PVOID)]
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class OVERLAPPED(Structure):
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_anonymous_ = ['_offset_union']
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_fields_ = [
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('Internal', ULONG_PTR),
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('InternalHigh', ULONG_PTR),
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('_offset_union', _OFFSET_UNION),
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('hEvent', HANDLE)]
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LPOVERLAPPED = POINTER(OVERLAPPED)
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# --- Define function prototypes for extra safety ---
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LockFileEx = windll.kernel32.LockFileEx
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LockFileEx.restype = BOOL
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LockFileEx.argtypes = [HANDLE, DWORD, DWORD, DWORD, DWORD, LPOVERLAPPED]
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UnlockFileEx = windll.kernel32.UnlockFileEx
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UnlockFileEx.restype = BOOL
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UnlockFileEx.argtypes = [HANDLE, DWORD, DWORD, DWORD, LPOVERLAPPED]
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elif os.name == 'posix':
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import fcntl
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LOCK_SH = fcntl.LOCK_SH # shared lock
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if os.name == 'nt':
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def lock(file, flags):
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""" Return True on success, False otherwise """
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hfile = msvcrt.get_osfhandle(file.fileno())
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# LockFileEx is not supported on all Win32 platforms (Win95, Win98,
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# WinME).
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# If it's not supported, win32file will raise an exception.
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# Try LockFileEx first, as it has more functionality and handles
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# blocking locks more efficiently.
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try:
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win32file.LockFileEx(hfile, flags, 0, 0xFFFF0000, __overlapped)
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except win32file.error, e:
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import winerror
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# Propagate upwards all exceptions other than not-implemented.
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if e[0] != winerror.ERROR_CALL_NOT_IMPLEMENTED:
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raise e
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# LockFileEx is not supported. Use LockFile.
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# LockFile does not support shared locking -- always exclusive.
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# Care: the low/high length params are reversed compared to
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# LockFileEx.
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if not flags & LOCK_EX:
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import warnings
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warnings.warn("PortaLocker does not support shared "
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"locking on Win9x", RuntimeWarning)
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# LockFile only supports immediate-fail locking.
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if flags & LOCK_NB:
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win32file.LockFile(hfile, 0, 0, 0xFFFF0000, 0)
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else:
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# Emulate a blocking lock with a polling loop.
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import time
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while 1:
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# Attempt a lock.
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try:
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win32file.LockFile(hfile, 0, 0, 0xFFFF0000, 0)
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break
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except win32file.error, e:
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# Propagate upwards all exceptions other than lock
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# violation.
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if e[0] != winerror.ERROR_LOCK_VIOLATION:
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raise e
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# Sleep and poll again.
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time.sleep(0.1)
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# TODO: should this return the result of the lock?
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overlapped = OVERLAPPED()
117+
if LockFileEx(hfile, flags, 0, 0, 0xFFFF0000, byref(overlapped)):
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return True
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else:
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return False
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def unlock(file):
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hfile = msvcrt.get_osfhandle(file.fileno())
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# UnlockFileEx is not supported on all Win32 platforms (Win95, Win98,
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# WinME).
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# If it's not supported, win32file will raise an api_error exception.
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try:
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win32file.UnlockFileEx(hfile, 0, 0xFFFF0000, __overlapped)
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except win32file.error, e:
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import winerror
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# Propagate upwards all exceptions other than not-implemented.
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if e[0] != winerror.ERROR_CALL_NOT_IMPLEMENTED:
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raise e
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# UnlockFileEx is not supported. Use UnlockFile.
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# Care: the low/high length params are reversed compared to
120-
# UnLockFileEx.
121-
win32file.UnlockFile(hfile, 0, 0, 0xFFFF0000, 0)
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overlapped = OVERLAPPED()
125+
if UnlockFileEx(hfile, 0, 0, 0xFFFF0000, byref(overlapped)):
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return True
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else:
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return False
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elif os.name =='posix':
124131
def lock(file, flags):
125-
fcntl.flock(file.fileno(), flags)
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# TODO: should this return the result of the lock?
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if fcntl.flock(file.fileno(), flags) == 0:
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return True
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else:
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return False
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def unlock(file):
129-
fcntl.flock(file.fileno(), fcntl.LOCK_UN)
138+
if fcntl.flock(file.fileno(), fcntl.LOCK_UN) == 0:
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return True
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else:
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return False
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if __name__ == '__main__':
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from time import time, strftime, localtime

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