title: ValueErrors: need more than 3 values to unpackk
body: <p>the goal of this code is to match <code>year_link</code> and <code>tla_2</code> and output variables <code>from_, to, digit, name2, min_value, max_value</code>. I am using a CSV file, that's where the data is being read from. It is posted here: <a href="https://i.stack.imgur.com/YOEGG.jpg" rel="nofollow noreferrer">Excel Sheet</a> Unfortunately I receive this error:</p>
  
  <pre><code>Traceback (most recent call last):
  File "C:/Users/RM/Desktop/win6.py", line 150, in &lt;module&gt;
  for from_,to,digit,name2,min_value,max_value in voltage_envelopes[tla_2]:
  ValueError: need more than 3 values to unpack.
  </code></pre>
  
  <p>-</p>
  
  <pre><code>data = list(csv.reader(open(LOAD_GEN_DATAFILE)))
  year = raw_input(" ")
  location=raw_input(" ")
  for row in data:
      year_link, from_,to,digit,name2,tla_2,min_value,max_value,last_bus = row[7:16]
      year_link = year
      tla_2=location
      if year_link not in mydict:
          mydict[year_link]={}
  
      voltage_envelopes=mydict[year_link]
  
      if tla_2 not in voltage_envelopes:
          voltage_envelopes[tla_2]=[]
  
      voltage_envelopes[tla_2].append((from_,to,digit,name2,min_value,max_value))
  
  if year_link in mydict and tla_2 in mydict[year_link]:
       voltage_envelopes=mydict[year_link]
  
       for from_,to,digit,name2,min_value,max_value in voltage_envelopes[tla_2]:
           from_=int(from_)
           to=int(to)
           min_value=float(min_value)
           max_value=float(max_value)
           digit=int(digit)
  
           output = 'From Bus #: {}\tTo Bus #: {}\t Area Station: {}\t VMIN: {} pu\tVMAX: {} pu\t' 
           print(output.format(from_, to,name2, min_value, max_value))
           print("\n")
  
          #_c=psspy.getdefaultchar()
          #_i=psspy.getdefaultint()
          #_f=psspy.getdefaultreal()
          #psspy.two_winding_chng_4(from_,to,'%d'% digit,[_i,_i,_i,_i,_i,_i,_i,_i,_i,_i,_i,_i,_i,_i,_i],[_f,_f,_f,_f,_f,_f,_f,_f,_f,_f,_f,_f,_f,_f,_f,_f,_f,_f,_f, max_value, min_value,_f,_f,_f],[])
  else:
      exit
  </code></pre>