human
I am working on the file "Chapter 1 - The Python Data Model.ipynb".
The first task is:
He talks about other dunder methods as well. In Java, Object's toString method is certainly one of the most well-known methods. In Python, this would be str and repr, two methods that are similar but have slightly different goals.
An example may make this clearer.
Can you write Python program for it?
 ... Write me a the Python program you requested?
assistant
#Here is the Python program you requested.

from datetime import timedelta

class Duration:
    def __init__(self, milliseconds):
        self._duration_in_milliseconds = milliseconds
        
    def __repr__(self):
        # return unambiguous string that mimics the source code to construct the object back
        return "Duration({0})".format(self._duration_in_milliseconds)
    
    def __str__(self):
        return str(timedelta(milliseconds=self._duration_in_milliseconds))
    
a_billion_milliseconds = Duration(1_000_000_000)
"'{0}' is unambiguous, '{1}' is human-friendly".format(repr(a_billion_milliseconds), str(a_billion_milliseconds))