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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 create_site(sitename):
 """Create a new site directory and init Yass"""

    sitepath = os.path.join(CWD, sitename)
    if os.path.isdir(sitepath):
        print("Site directory '%s' exists already!" % sitename)
    else:
        print("Creating site: %s..." % sitename)
        os.makedirs(sitepath)
        copy_resource("skel/", sitepath)
        stamp_yass_current_version(sitepath)
        print("Site created successfully!")
        print("CD into '%s' and run 'yass serve' to view the site" % sitename)

    footer()