[Tutor] If/elif/else when a list is empty

[aeneas24 at priest.com]

Hi,

I'm parsing IMDB movie reviews (each movie is in its own text file). In my script, I'm trying to extract genre information. Movies have up to three categories of genres--but not all have a "genre" tag and that fact is making my script abort whenever it encounters a movie text file that doesn't have a "genre" tag. 

I thought the following should solve it, but it doesn't. The basic question is how I say "if genre information doesn't at all, just make rg1=rg2=rg3="NA"?

rgenre = re.split(r';', rf.info["genre"]) # When movies have genre information they store it as <genre>Drama;Western;Thriller</genre>

if len(rgenre)>0:
          if len(rgenre)>2:
              rg1=rgenre[0]
              rg2=rgenre[1]
              rg3=rgenre[2]
          elif len(rgenre)==2:
              rg1=rgenre[0]
              rg2=rgenre[1]
              rg3="NA"
          elif len(rgenre)==1:
              rg1=rgenre[0]
              rg2="NA"
              rg3="NA"
   else len(rgenre)<1: # I was hoping this would take care of the "there is no genre information" scenario but it doesn't
           rg1=rg2=rg3="NA"

This probably does a weird nesting thing, but even simpler version I have tried don't work. 

Thanks very much for any help!

Tyler
      



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