## Can You Enhance Python\'s Built-in Types with Custom Methods and Attributes?

Can Custom Methods and Attributes Be Added to Built-in Python Types?

In Python, it is not possible to directly modify the built-in data types such as dicts. However, a technique known as "monkey patching" allows a subclass to be created and substituted into the global namespace. This provides an enhanced version of the original data type.

Monkey Patching Technique

1. Create a subclass that extends the original data type, adding desired methods or attributes.
2. Replace the original type with the subclass in the built-in namespace using __builtin__.

Example: Adding a first_last() Method to str

<code class="python"># Built-in namespace
import __builtin__

# Extended subclass
class mystr(str):
    def first_last(self):
        if self:
            return self[0] + self[-1]
        else:
            return ''

# Substitute the original str with the subclass on the built-in namespace    
__builtin__.str = mystr

print(str(1234).first_last())  # Output: 14
print(str(0).first_last())  # Output: 00
print(str('').first_last())  # Output: ''</code>

Limitations:

This technique has a few caveats:

• Objects created with literal syntax (e.g., '0') will not have the added methods/attributes.
• The original version of the type is lost and cannot be restored easily.

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