eval to import a module

Question:

I can’t import a module using the eval() function.

So, I have a function where if I do import vfs_tests as v it works. However, the same import using eval() like eval('import vfs_tests as v') throws a syntax error.

Why is this so?

Asked By: Siddharth

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Answers:

Use exec:

exec 'import vfs_tests as v'

eval works only on expressions, import is a statement.

exec is a function in Python 3 : exec('import vfs_tests as v')

To import a module using a string you should use importlib module:

import importlib
mod = importlib.import_module('vfs_tests')

In Python 2.6 and earlier use __import__.

Answered By: Ashwini Chaudhary

Actually. if you absolutely need to import using eval (for example, code injection), you can do it as follow in Python 3, since exec is a function:

eval("exec('import whatever_you_want')")

For example:

>>> eval('exec("from math import *")')
>>> sqrt(2)
1.4142135623730951
Answered By: Frederic

My little trick if you want to pass all the code as string to eval function:

>>> eval('exec("import uuid") or str(uuid.uuid4())')
'bc4b921a-98da-447d-be91-8fc1cebc2f90'
>>> eval('exec("import math") or math.sqrt(2)')
1.4142135623730951
Answered By: Edmund Wang

You can use __import__ inside of eval to import something.

eval("__import__('os').system('ls')")
Answered By: qwerty_url
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