code: def parse_dependency_links(file_name):
      
      dependency_links = []
      with open(file_name) as f:
          for line in f:
              if re.match(r'\s*-[ef]\s+', line):
                  dependency_links.append(re.sub(r'\s*-[ef]\s+',\
                          '', line))
      return dependency_links
docs: from:
          http://cburgmer.posterous.com/pip-requirementstxt-and-setuppy