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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 remove_custom_binding(self, key_name, needs_prefix=False):
 """ Remove custom key binding for a key. :param key_name: Pymux key name, for instance "C-A". """

        k = (needs_prefix, key_name)

        if k in self.custom_bindings:
            self.custom_key_bindings.remove(self.custom_bindings[k].handler)
            del self.custom_bindings[k]