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idle session

Let’s use IDLE to create some object instances from a new class that you’ll define. Start by creating a small class
called Athlete:
Note the default values for
>>> class Athlete: two of the arguments.
def __init__(self, a_name, a_dob=None, a_times=[]):
self.name = a_name Three attributes are initialized and assigned to three class
self.dob = a_dob attributes using the supplied argument data.
self.times = a_times
With the class defined, create two unique object instances which derive their characteristcs from the Athlete
class:
>>> sarah = Athlete('Sarah Sweeney', '2002-6-17', ['2:58', '2.58', '1.56'])
>>> james = Athlete('James Jones')
Create two unique athletes (with
>>> type(sarah) “james” using the default argument
<class '__main__.Athlete'> Confirm that both “sarah” and values).
>>> type(james) “james” are athletes.
<class '__main__.Athlete'>
Even though sarah and james are both athletes and were created by the Athlete class’s factory function,
they are stored at different memory addreses:
>>> sarah
differ from the values reported on yours. The key point is
<__main__.Athlete object at 0x14d23f0> These are the memory addresses on our computer, which will
>>> james the memory address for “sarah” and “james” differ.
<__main__.Athlete object at 0x14cb7d0>

Now that sarah and james exist as object instances, you can use the familiar dot notation to access the
attributes associated with each:

>>> sarah.name
'Sarah Sweeney'
>>> james.name
'James Jones'
>>> sarah.dob
'2002-6-17'
>>> james.dob The “james” object instance has no value for
“dob”, so nothing appears on screen.
>>> sarah.times
['2:58', '2.58', '1.56']
>>> james.times
[]

194 Chapter 6