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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 attach(self, dwProcessId):
 """ Attaches to an existing process for debugging. @see: L{detach}, L{execv}, L{execl} @type dwProcessId: int @param dwProcessId: Global ID of a process to attach to. @rtype: L{Process} @return: A new Process object. Normally you don't need to use it now, it's best to interact with the process from the event handler. @raise WindowsError: Raises an exception on error. Depending on the circumstances, the debugger may or may not have attached to the target process. """


        # Get the Process object from the snapshot,
        # if missing create a new one.
        try:
            aProcess = self.system.get_process(dwProcessId)
        except KeyError:
            aProcess = Process(dwProcessId)

        # Warn when mixing 32 and 64 bits.
        # This also allows the user to stop attaching altogether,
        # depending on how the warnings are configured.
        if System.bits != aProcess.get_bits():
            msg = "Mixture of 32 and 64 bits is considered experimental." \
                  " Use at your own risk!"
            warnings.warn(msg, MixedBitsWarning)

        # Attach to the process.
        win32.DebugActiveProcess(dwProcessId)

        # Add the new PID to the set of debugees.
        self.__attachedDebugees.add(dwProcessId)

        # Match the system kill-on-exit flag to our own.
        self.__setSystemKillOnExitMode()

        # If the Process object was not in the snapshot, add it now.
        if not self.system.has_process(dwProcessId):
            self.system._add_process(aProcess)

        # Scan the process threads and loaded modules.
        # This is prefered because the thread and library events do not
        # properly give some information, like the filename for each module.
        aProcess.scan_threads()
        aProcess.scan_modules()

        # Return the Process object, like the execv() and execl() methods.
        return aProcess