def get_inputs( filename ):
    """
    The input file is in the form of lines of instructions with a command
    and a value. For each line in the input file, an instructions list is
    created which contains a list [command, value]
    e.g.: instructions = [ ['acc','+50'], ['acc','-11'], .... ]
    """
    with open( filename, 'r') as input_file:
        lines = input_file.read().splitlines()
    instructions = []
    for line in lines:
        instructions.append( line.split(' ') )
    return instructions