def build_urls(base, appendages):
 urls = [base]
 for i in range(len(appendages)):
  urls.append((base + ''.join(appendages[:(i + 1)])))
 return urls

def build_urls ( base , appendages ) : urls = [ base ] for i in range ( len ( appendages ) ) : urls . append ( ( base + '' . join ( appendages [ : ( i + 1 ) ] ) ) ) return urls
many of our urls build off each other: e .