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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 stalk_at(self, pid, address, action = None):
 """ Sets a one shot code breakpoint at the given process and address. If instead of an address you pass a label, the breakpoint may be deferred until the DLL it points to is loaded. @see: L{break_at}, L{dont_stalk_at} @type pid: int @param pid: Process global ID. @type address: int or str @param address: Memory address of code instruction to break at. It can be an integer value for the actual address or a string with a label to be resolved. @type action: function @param action: (Optional) Action callback function. See L{define_code_breakpoint} for more details. @rtype: bool @return: C{True} if the breakpoint was set immediately, or C{False} if it was deferred. """

        bp = self.__set_break(pid, address, action, oneshot = True)
        return bp is not None