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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 connect(self, key, func):
 """Connect a function to the given formatoption Parameters key: str The rcParams key func: function The function that shall be called when the rcParams key changes. It must accept a single value that is the new value of the key."""

        key = self._get_depreceated(key)[0]
        if key is not None:
            self._connections[key].append(func)