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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(self, parent, child):
 """Remove a dependency between parent and child. Parameters parent : boolean instance of :class:`katcp.Sensor` The sensor that used to depend on child. child : boolean instance of :class:`katcp.Sensor` or None The sensor parent used to depend on. """

        self.remove_links(parent, (child,))
        if parent not in self and parent in self._parent_to_not_ok:
            del self._parent_to_not_ok[parent]
        if child not in self and child in self._parent_to_not_ok:
            del self._parent_to_not_ok[child]