text: fin=open("Street_Centrelines.csv","r")
  def easy(fin):
          list1=[]
          for line in fin:
                  line=line.split(",")
                  list1.append((line[2],line[4],line[6],line[7]))
          return list1
  print(easy(fin))
  fin=open("Street_Centrelines.csv","r")
  def histogram(fin):
          d=dict()
          for line in fin:
                  line=line.split(",")
                  if line[12] not in d:
                          d[line[12]]=1
                  else:
                          d[line[12]]+=1
          return d        
  print(histogram(fin))
  
  
  fin=open("Street_Centrelines.csv","r")
  def own(fin):
  	s=set()
  	for line in fin:
  		line=line.split(",")
  		s.add(line[11])
  	return s
  print(own(fin))
  