How Can I Safely Access Environment Variables in Python?

Accessing Environment Variables in Python

Environment variables provide a convenient way to store and access system-wide settings and user preferences. Python offers several methods for accessing these variables.

One approach is through the os.environ object, a dictionary-like object containing all available environment variables. To retrieve the value of a specific variable, simply use its name as the key:

import os
print(os.environ['HOME'])

To view a comprehensive list of all environment variables:

print(os.environ)

However, attempting to access a non-existent key will raise a KeyError. To avoid this, several options are available:

• get() method: Returns None if the key does not exist.

print(os.environ.get('KEY_THAT_MIGHT_EXIST'))

• get() method with default value: Specifies a default value to return if the key is missing.

print(os.environ.get('KEY_THAT_MIGHT_EXIST', default_value))

• getenv() function: Similar to get() with default value.

print(os.getenv('KEY_THAT_MIGHT_EXIST', default_value))

By employing these methods, you can easily access and manage environment variables in your Python applications.

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