How Have Python 3\'s Import Statement Enhancements Improved Code Clarity and Reduced Ambiguity?

Understanding Import Statement Enhancements in Python 3

Background:

The Python 3 development team implemented changes to the import statement in Python 2, aimed at improving its clarity and reducing ambiguity.

Relative Imports:

• What is a relative import?

  • When importing a module within a package that is relative to the current script or package.

• Example:

  • In the example directory structure, derived.py would previously import BaseThing from base.py using the statement:

    from base import BaseThing

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  • Python 3 requires explicit relative imports:

    from .base import BaseThing

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  • The .base prefix explicitly indicates importing from the module directory of the current module.

Star Imports:

• Restrictions in Python 3:

  • Star imports (e.g., from x import *) are only permitted in module-level code.

• Use Case in Python 2:

  • In Python 2, star imports were allowed within functions to import multiple specific functions or classes at once.

• Example:

  • In Python 2, the following code was valid:

    def sin_degrees(x):
        from math import *
        return sin(degrees(x))

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  • Python 3 requires a more explicit approach:

    def sin_degrees(x):
        from math import sin, degrees
        return sin(degrees(x))

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