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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 merge(self, other):
 """Merge another translation into this catalog."""

        if not getattr(other, '_catalog', None):
            return  # NullTranslations() has no _catalog
        if self._catalog is None:
            # Take plural and _info from first catalog found
            self.plural = other.plural
            self._info = other._info.copy()
            self._catalog = other._catalog.copy()
        else:
            self._catalog.update(other._catalog)