# functions

def display_inventory(inv_type, chunky, skybar, valomilk, zagnut):
    print()
    print(inv_type.capitalize() + ' inventory')
    print('-----------------')
    print('{:8s} {:8d}'.format('Chunky', chunky))
    print('{:8s} {:8d}'.format('Skybar', skybar))
    print('{:8s} {:8d}'.format('Valomilk', valomilk))
    print('{:8s} {:8d}'.format('zagnut', zagnut))
    print('-----------------')

# main algorithm

# read names of data files

initial_inventory = input('Name of file with the week\'s initial inventory: ')
transactions      = input('Name of file with the week\'s transactions     : ')
updated_inventory = input('Name of file with the week\'s updated inventory: ')

# read beginning inventory file
#      this could be a function that returns a comma-separated string

initial_inventory_file = open(initial_inventory, 'r')
for line in initial_inventory_file:
    bar,count = line.strip().lower().split()
    if bar == 'chunky':
        chunky = int(count)
    elif bar == 'skybar':
        skybar = int(count)
    elif bar == 'valomilk':
        valomilk = int(count)
    else: # bar == 'zagnut':
        zagnut = int(count)
initial_inventory_file.close()

# display beginning inventory

display_inventory('Initial', chunky, skybar, valomilk, zagnut)

# process week's transactions
#   compute running total of change to each
#   count number of transactions of each type
# display the number of  transactions processed
# display ending inventory
# write ending inventory file