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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 database_caller_creator(self, host, port, name=None):
        '''creates a mongodb database
        returns the related connection object
        which will be later used to spawn the cursor
        '''

        client = pymongo.MongoClient(host, port)

        if name:
            db = client[name]
        else:
            db = client['mongodb_' + str_generator(self)]

        return db