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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 get_users_in_project(self, projectname):
 """ Get list of users in project from MAM. """

        ds_project = self.get_project(projectname)
        if ds_project is None:
            logger.error(
                "Project '%s' does not exist in MAM" % projectname)
            raise RuntimeError(
                "Project '%s' does not exist in MAM" % projectname)

        user_list = []
        if ds_project["Users"] != "":
            user_list = ds_project["Users"].lower().split(",")
        return user_list