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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 mirror():
 """Get mirror from slackpkg mirrors file """

    slack_mirror = read_config(
        read_file("{0}{1}".format(etc_slackpkg, "mirrors")))
    if slack_mirror:
        return slack_mirror + changelog_txt
    else:
        print("\nYou do not have any mirror selected in /etc/slackpkg/mirrors"
              "\nPlease edit that file and uncomment ONE mirror.\n")
        return ""