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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 need_completion_refresh(queries):
 """Determines if the completion needs a refresh by checking if the sql statement is an alter, create, drop or change db."""

    tokens = {
        'use', '\\u',
        'create',
        'drop'
    }

    for query in sqlparse.split(queries):
        try:
            first_token = query.split()[0]
            if first_token.lower() in tokens:
                return True
        except Exception:
            return False