I'm trying to figure out a way to define my function for loaning a book within a class. This is what I have so far:
class Library:
# the class constructor
def __init__(self, books, patrons):
self.books=books
self.patrons=patrons
def __str__(self):
s="Patron("
for patron in self.patrons:
s+=str(patron) + ', '
if len(self.patron) != 0:
s= s[:-2]
s+=']'
for book in self.books:
s+=str(book) + ', '
if len(self.books) != 0:
s= s[:-2]
s+='])'
return s
and I have my function:
def loan_book(self, patron_id, book_id):
existence= False
for i in self.patrons:
if i.patron_id==patron_id:
return True
raise LookupError
for i in self.books:
if i.book_id==book_id:
return True
raise LookupError
for i in patron:
if i.book_id==book_id:
raise DuplicateIdError()
self.books.remove(book_id)
patron.books.append(book_id)
I just want to make sure it is correct. any help?