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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 default_database(ctx: click.Context, _param: Parameter, value: Optional[str]):
 """Try to guess a reasonable database name by looking at the repository path"""

    if value:
        return value

    if ctx.params["repository"]:
        return os.path.join(ctx.params["repository"], DB.DEFAULT_DB_FILE)

    raise click.BadParameter("Could not guess a database location")