def roles(self, roles_list):
if roles_list and isinstance(roles_list, list):<EOL><INDENT>self.roles = [].extend(roles_list)<EOL><DEDENT>elif roles_list and isinstance(roles_list, basestring):<EOL><INDENT>self.roles = [role.lower() for role in roles_list.split('<STR_LIT:U+002C>')]<EOL><DEDENT>
Set the roles for the current launch.

Full list of roles can be found here:
http://www.imsglobal.org/LTI/v1p1/ltiIMGv1p1.html#_Toc319560479

LIS roles include:
* Student
* Faculty
* Member
* Learner
* Instructor
* Mentor
* Staff
* Alumni
* ProspectiveStudent
* Guest
* Other
* Administrator
* Observer
* None