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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 hook_function(self, pid, address, preCB = None, postCB = None, paramCount = None, signature = None):
 """ Sets a function hook at the given address. If instead of an address you pass a label, the hook may be deferred until the DLL it points to is loaded. @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 preCB: function @param preCB: (Optional) Callback triggered on function entry. The signature for the callback should be something like this:: def pre_LoadLibraryEx(event, ra, lpFilename, hFile, dwFlags):
 # return address ra = params[0] szFilename = event.get_process().peek_string(lpFilename) Note that all pointer types are treated like void pointers, so your callback won't get the string or structure pointed to by it, but the remote memory address instead. This is so to prevent the ctypes library from being "too helpful" and trying to dereference the pointer. To get the actual data being pointed to, use one of the L{Process.read} methods. @type postCB: function @param postCB: (Optional) Callback triggered on function exit. The signature for the callback should be something like this:: def post_LoadLibraryEx(event, return_value):
 @type paramCount: int @param paramCount: (Optional) Number of parameters for the C{preCB} callback, not counting the return address. Parameters are read from the stack and assumed to be DWORDs in 32 bits and QWORDs in 64. This is a faster way to pull stack parameters in 32 bits, but in 64 bits (or with some odd APIs in 32 bits) it won't be useful, since not all arguments to the hooked function will be of the same size. For a more reliable and cross-platform way of hooking use the C{signature} argument instead. @type signature: tuple @param signature: (Optional) Tuple of C{ctypes} data types that constitute the hooked function signature. When the function is called, this will be used to parse the arguments from the stack. Overrides the C{paramCount} argument. @rtype: bool @return: C{True} if the hook was set immediately, or C{False} if it was deferred. """

        try:
            aProcess = self.system.get_process(pid)
        except KeyError:
            aProcess = Process(pid)
        arch = aProcess.get_arch()
        hookObj = Hook(preCB, postCB, paramCount, signature, arch)
        bp = self.break_at(pid, address, hookObj)
        return bp is not None