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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 unbind(topic, func):

 """
 Remove receiver function
 """

    if topic in _receivers:
        receivers = _receivers[topic]
        for i in range(len(receivers)-1, -1, -1):
            nice, f = receivers[i]
            if (callable(func) and f['func'] == func) or (f['func_name'] == func):
                del receivers[i]
                return