In page 194, the code says:
class Athlete: def __init__(self, a_name, a_dob=None, a_times=):
This generates errors when a an instance of the class is initialized with the default value "  " and later another instance is also initialized with the default value.
class Test: def __init__(self, items=): self.items=items
>>>t = Test() >>>t.items.append("stuff") >>>t.items ['stuff'] >>>t2 = Test() >>>t2.items ['stuff']
Here is an explanation:
which says that the correct way is to initialize mutable objects like this:
class Test2: def __init__(self, items=None): if items: self.items=items else: self.items = 
This is not in the errata, so I guess it's not corrected.