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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 get(self, name, default=None):
 """ Returns an extension instance with a given name. In case there are few extensions with a given name, the first one will be returned. If no extensions with a given name are exist, the `default` value will be returned. :param name: (str) an extension name :param default: (object) a fallback value :returns: (object) an extension instance """

        try:
            value = self[name]
        except KeyError:
            value = default
        return value