Sets the label's text from the string str.
If characters in str are preceded by an underscore, they are underlined
indicating that they represent a keyboard accelerator called a mnemonic.
The mnemonic key can be used to activate another widget, chosen
automatically, or explicitly using gtk_label_set_mnemonic_widget().
Sets the label's text from the string str. If characters in str are preceded by an underscore, they are underlined indicating that they represent a keyboard accelerator called a mnemonic. The mnemonic key can be used to activate another widget, chosen automatically, or explicitly using gtk_label_set_mnemonic_widget().