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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 cli(ctx, overwrite):
 """Updates the local database with remote."""

    credentials_path = os.path.join(os.path.expanduser('~'), '.keep', '.credentials')
    if not os.path.exists(credentials_path):
        click.echo('You are not registered.')
        utils.register()
    else:
        utils.pull(ctx, overwrite)