What are some best practices for handling output from PHP functions in WordPress?

When handling output from PHP functions in WordPress, it is best practice to use output buffering to capture the output and then return it instead of directly echoing it. This helps in maintaining clean and organized code, preventing unexpected output, and allowing for easier debugging and modification.

// Start output buffering
ob_start();

// Call the PHP function
my_custom_function();

// Get the buffered output
$output = ob_get_clean();

// Return the output
return $output;