what does __str__ mean? in python code example

Example 1: python __repr__ meaning

>>>x=4
>>>repr(x)
'4'
>>>str(x)
'4'
>>>y='stringy'
>>>repr(y)
"'stringy'"
>>>str(y)
'stringy'

Example 2: python __repr__ meaning

>>>repr(y)
"'a string'"
>>>y2=eval(repr(y))
>>>y==y2
True