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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 generate_config(ctx):
 """ Generates a sample gitlint config file. """

    path = click.prompt('Please specify a location for the sample gitlint config file', default=DEFAULT_CONFIG_FILE)
    path = os.path.abspath(path)
    dir_name = os.path.dirname(path)
    if not os.path.exists(dir_name):
        click.echo(u"Error: Directory '{0}' does not exist.".format(dir_name), err=True)
        ctx.exit(USAGE_ERROR_CODE)
    elif os.path.exists(path):
        click.echo(u"Error: File \"{0}\" already exists.".format(path), err=True)
        ctx.exit(USAGE_ERROR_CODE)

    LintConfigGenerator.generate_config(path)
    click.echo(u"Successfully generated {0}".format(path))
    ctx.exit(0)