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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def isPIDValid(self, pid):
 """ Checks if a PID is associated with a running process """

        ## Slightly copied wholesale from http://stackoverflow.com/questions/568271/how-to-check-if-there-exists-a-process-with-a-given-pid
        ## Thanks to http://stackoverflow.com/users/1777162/ntrrgc and http://stackoverflow.com/users/234270/speedplane
        class ExitCodeProcess(ctypes.Structure):
            _fields_ = [('hProcess', ctypes.c_void_p),
                        ('lpExitCode', ctypes.POINTER(ctypes.c_ulong))]
        SYNCHRONIZE = 0x100000
        PROCESS_QUERY_LIMITED_INFORMATION = 0x1000
        process = self._kernel32.OpenProcess(SYNCHRONIZE|PROCESS_QUERY_LIMITED_INFORMATION, 0, pid)
        if not process:
            return False
        ec = ExitCodeProcess()
        out = self._kernel32.GetExitCodeProcess(process, ctypes.byref(ec))
        if not out:
            err = self._kernel32.GetLastError()
            if self._kernel32.GetLastError() == 5:
                # Access is denied.
                logging.warning("Access is denied to get pid info.")
            self._kernel32.CloseHandle(process)
            return False
        elif bool(ec.lpExitCode):
            # There is an exit code, it quit
            self._kernel32.CloseHandle(process)
            return False
        # No exit code, it's running.
        self._kernel32.CloseHandle(process)
        return True