3.1 Repr-esentation

Submit your answers with python ok -q q1 -u.

In What Would Python Display problems, always follow these rules:

For each of the expressions in the table below, write the output displayed by the interactive Python interpreter when the expression is valued. The output may have multiple lines or no lines.

• If an error occurs, write Error, but include all output displayed before the error.
• If an expression evaluates to a function value, write Function.
• If an expression would take forever to evaluate, write Forever.
• If the interpretor prints nothing, write Nothing.

Note: This is not the typical way repr is used, nor is this way of writing repr recommended. This problem is mainly just to make sure you understand how repr and str work.

class A:
    def __init__(self, x):
        self.x = x

    def __repr__(self):
         return self.x

    def __str__(self):
         return self.x * 2

class B:
    def __init__(self):
         print('boo!')
         self.a = []

    def add_a(self, a):
         self.a.append(a)

    def __repr__(self):
         print(len(self.a))
         ret = ''
         for a in self.a:
             ret += str(a)
         return ret

>>> A('one')
______

>>> print(A('one'))
______

>>> repr(A('two'))
______

>>> b = B()
______

>>> b.add_a(A('a'))
>>> b.add_a(A('b'))
>>> b
______