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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 add_permission(content_type, permission):
 """ Adds the passed in permission to that content type. Note that the permission passed in should be a single word, or verb. The proper 'codename' will be generated from that. """

    # build our permission slug
    codename = "%s_%s" % (content_type.model, permission)

    # sys.stderr.write("Checking %s permission for %s\n" % (permission, content_type.name))

    # does it already exist
    if not Permission.objects.filter(content_type=content_type, codename=codename):
        Permission.objects.create(content_type=content_type,
                                  codename=codename,
                                  name="Can %s %s" % (permission, content_type.name))