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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 _site_users():
 """ Get a list of site_n users """

    userlist = sudo("cat /etc/passwd | awk '/site/'").split('\n')
    siteuserlist = [user.split(':')[0] for user in userlist if 'site_' in user]
    return siteuserlist