docstr: add a new paragraph with text string
  
  Args:
      text (str): text string written to html,
                  with current global indent level
      link (int): link idx created earlier for internal anchor
      style (str): styles applied to the text
                  'B': bold,
                  'I': italic,
                  'U': underline,
                  or any combination of above
  Returns: HTML String
code: def add_paragraph(text: str, link=None, style=""):
      """
      add a new paragraph with text string
  
      Args:
          text (str): text string written to html,
                      with current global indent level
          link (int): link idx created earlier for internal anchor
          style (str): styles applied to the text
                      'B': bold,
                      'I': italic,
                      'U': underline,
                      or any combination of above
      Returns: HTML String
      """
      doc = Doc()
      with doc.tag("p"):
          if not (link is None):
              doc.attr(href=link)
          doc.asis(CustomHtml.__add_text(text=text, style=style))
      return doc.getvalue()
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  import datetime
  from yattag import Doc, indent
label_desc: Use image node_id 19 for calling the CustomHtml obj's underlying member method code with example usage: obj.add_paragraph(text, link, style) and returns: doc