code: def rst2md(text):
      
  
      top_heading = re.compile(r'^=+$\s^([\w\s-]+)^=+$', flags=re.M)
      text = re.sub(top_heading, r'# \1', text)
  
      math_eq = re.compile(r'^\.\. math::((?:.+)?(?:\n+^  .+)*)', flags=re.M)
      text = re.sub(math_eq,
                    lambda match: r'$${0}$$'.format(match.group(1).strip()),
                    text)
      inline_math = re.compile(r':math:`(.+)`')
      text = re.sub(inline_math, r'$\1$', text)
  
      return text
docs: Converts the RST text from the examples docstrigs and comments
      into markdown text for the IPython notebooks