42_flexible_dict.py

"""
In this exercise, we’ll also implement a subclass of dict, which I call 
FlexibleDict. Dict keys are Python objects, and as such are identified with a 
type. So if you use key 1 (an integer) to store a value, then you can’t use 
key '1' (a string) to retrieve that value. But FlexibleDict will allow for 
this. If it doesn’t find the user’s key, it will try to convert the key to 
both str and int before giving up
"""

from collections import UserDict

class FlexibleDict(UserDict):
    def __getitem__(self, key):
        try:
            if key in self:
                pass
            elif str(key) in self:
                key = str(key)
            elif int(key) in self:
                key = int(k)
        except ValueError:
            pass
        return UserDict.__getitem__(self, key)
    
    
d = {1: '1', 2: '2'}

fd = FlexibleDict()
 
fd['a'] = 100
print(fd['a'])    
 
fd[5] = 500
print(fd[5])      
  
 
fd['1'] = 100     
print(fd[1])