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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 listDatabases(self):
 """Returns a list of databases available across all sessions."""

        iter = self._jcatalog.listDatabases().toLocalIterator()
        databases = []
        while iter.hasNext():
            jdb = iter.next()
            databases.append(Database(
                name=jdb.name(),
                description=jdb.description(),
                locationUri=jdb.locationUri()))
        return databases