python - How to select records in the case of a many to many relation with ponyorm -

i new ponyorm.

suppose have these 2 classes , many-to-many relation among them:

class student(db.entity):     id = primarykey(str)     name = required(str)     courses = set("course")  class course(db.entity):     id = primarykey(str)     name = required(str)     semester = required(int)     students = set(student) 

and want select courses followed particular student. is:

student = student.select(lambda s: s.id == id).get() courses = course.select(lambda c: c.students == student).get() 

and error:

incomparable types 'set of student' , 'student' in expression: c.students == student 

what correct way this? thanks

i don't know exact library think issue c.students specifies set of students testing equality doesn't make sense.

you might want change second line (i didn't test though):

course.select(lambda c: student in c.students).get() 

this leaves me wondering if there better way this. if trying retrieve courses specific students attends why don't retrieve courses field variable student?

something like

student = student.select(lambda s: s.id == id).get() student.courses #