How Can You Achieve the Functionality of PHP\'s `compact()` and `extract()` in Python?

Equivalents to PHP's Compact() and Extract() in Python

PHP's compact() and extract() functions provide a convenient way to create a hashtable from specific symbol table values and vice versa. While Python does not have direct equivalents, there are methods to achieve similar functionality.

Creating a Hash from Subset of Variables

The compact() function can be implemented using Python's introspection module:

<code class="python">import inspect

def compact(*names):
    caller = inspect.stack()[1][0]  # Caller of compact()
    vars = {}
    for n in names:
        if n in caller.f_locals:
            vars[n] = caller.f_locals[n]
        elif n in caller.f_globals:
            vars[n] = caller.f_globals[n]
    return vars</code>

Extracting Values into Variables

The extract() function, however, is not as straightforward. While it was once possible to assign variables directly from a dictionary, modern interpreters no longer support this practice.

Considerations

Using these methods goes against Python's principles of explicitness, simplicity, and transparency. They may be appropriate for specific scenarios, such as debugging or frameworks with dynamic variable creation. However, they should be used sparingly as they can make code less readable and maintainable.

Python offers more Pythonic alternatives for handling variables, such as using namedtuples, classes with attributes, or dictionaries. These approaches provide greater control, encapsulation, and flexibility.

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