Python Parse a Simple Key-Value String

A local configuration file contains a setting such as mode=fast.

What You Need to Understand

Use partition("=") to split a simple key-value line at its first equals sign, leaving additional equals signs in the value. Validate that the separator exists and that the key is not blank.

When to Use It

A local configuration file contains a setting such as mode=fast.

Step-by-Step Python Example

setting_line = "region=west=2"
name, separator, value = setting_line.partition("=")
if separator and name:
    print(f"Setting {name} has value {value}")
else:
    print("Invalid setting")

How the Example Works

The key is region; the value is west=2 because only the first separator is used.

Example Output

Setting region has value west=2
('theme', 'dark')

A Second Example

Compare this smaller variation with the main example, then experiment with your own values.

line = "theme=dark"
key, found, value = line.partition("=")
print((key, value) if found else None)

Important Behavior and Edge Cases

This example is not a complete INI parser: it does not handle comments, escapes or nested syntax. Use configparser for real INI files.

Try It Yourself

Handle lines that have no equals sign and lines whose key contains whitespace.

Common Beginner Mistakes

This example is not a complete INI parser: it does not handle comments, escapes or nested syntax. Use configparser for real INI files.
Applying a string method before defining whether text is intended for display, comparison, parsing, or input validation.

Key Takeaways

Use partition("=") to split a simple key-value line at its first equals sign, leaving additional equals signs in the value.
The key is region; the value is west=2 because only the first separator is used.
This example is not a complete INI parser: it does not handle comments, escapes or nested syntax.