How to Import Python Module from String Name

In this Python tutorial, we will explore how to import a Python Module using a string representation of its name. We will achieve this task using the Python importlib module, which provides us with the required functionality.

It is important to note that this library is only available on Python 2.7, and Python 3.1 and above.

Import Python Module using importlib

Normally, when we want to import modules/libraries in Python, we follow the below format.

import matplotlib

However, we may wish to import libraries during run-time, or based on user input. This may lead us to trying the following approach(es).

import "matplotlib"      # Wrong

str = "matplotlib"
import str               # Wrong

Both of the above approaches are wrong, and will not work as intended. This is where the Python importlib library comes in.

We will be using the importlib library’s import_module() function. This function takes as parameter, a string that represents the library you wish to import.

Let’s take a look at how to import a module using this function.

import importlib

lib = importlib.import_module("random")

for i in range(5):
    print(lib.randint(1, 10))

Once you have called import_module() function, it will return a library object. Every time you want to use a function from the imported library, you must do it through the library object.

In the above example, we imported the random library, used to generate random numbers. It has a variety of different functions, one of which is randint(). Normally we might do random.randint() to call this, but when using importlib, we need to do lib.randint(). (lib is an arbitrary name)

More about importlib

Some special cases can arise, such as when you need to import a sub-module. The below code shows how you would go about doing so.

import importlib

lib = importlib.import_module("matplotlib.pyplot")

lib.plot([1, 2, 3, 4], [1, 4, 9, 16])
lib.show()

Normally, this would have been the following statement.

import matplotlib.pyplot

For more information about importlib, please refer to the dedicated section for the Python importlib module.

This marks the end of the “Import Python Module from String” Tutorial. Any suggestions or contributions for CodersLegacy are more than welcome. Questions regarding the tutorial content can be asked in the comments section.