def getLocations(fileName):
       """
       getLocations takes a filename as input (fileName). filename is a txt file 
       that is structured like this: 
       location1: 1,2,3,4
       location2: 3,4,5,6
       where the numbers are specific cells, cell faces, or face points 
       the function returns a dictionary (locations) where the key is the location i.e location 1 and the key 
       is the cells or faces for that location, i.e 1,2,3,4.
   
       """
       infile = open(fileName, 'r') # Open text file 
       locations = {} # Create dictionary  
       # For loop 
       for line in infile.readlines():
           location = line.split(":")[0] # Split into location and cell values [0] left of colon 
           locations[location] = list(map(int,line.split(":")[1].split(','))) # [1] Right of colon number  
           
       infile.close()
       
       return locations