docs: def tprint( text, layers, markup_settings = None ):
      ''' Formats given text, adding a special ( ANSI-terminal compatible ) markup
          to the annotations of given layers, and prints the formatted text to the 
          screen. 
          *) layers is a list containing names of the layers to be preformatted in 
             the text (these layers must be present in Text);
          *) markup_settings should be a list containing annotation options for each
             layer: one dict with options per layer;
             One dict can contain the following visualization options:
             * 'bracket' : True -- annotations will be surrounded with brackets; This 
                                   works in any terminal;
             * 'underline' : True -- annotations will be underlined; This works in ANSI 
                                     compatible terminal;
             * 'color' : ('red', 'green', 'blue' etc. ) -- annotated text will be 
                         displayed in given color; this works in ANSI compatible 
                         terminal;
          *) Alternatively, if markup_settings is undefined, up to 12 layers can be 
             visualized following the default settings;
          
          Parameters
          ----------
          text: Text
             a text object. Must contain given layers;
          layer: list of str
             list of layer names to be visualised;
          markup_settings: list of dict
             list of dictionaries containing user-defined visualization options;
             (one dict per layer)
      '''
      if markup_settings and len(layers) != len(markup_settings):
         raise Exception(' Input arguments layers and markup_settings should be equal size lists.')
      elif not markup_settings and len(layers) <= len(default_markup_settings):
         # Use a subset from default markup settings
         markup_settings = default_markup_settings[0:len(layers)]
      elif not markup_settings:
         raise Exception(' Input argument markup_settings not defined.')
      print( _preformat(text, layers, markup_settings=markup_settings) )