s = 'single quotes'
s = "double quotes"
s = """triple quotes are
used for multi-line
strings
"""
s = r'raw strings start with r and backslash \ is preserved'
s = '\t\n'  # tab + newline
s = r'\t\n'  # a string with four characters: \t\n

if sys.platform.startswith('win'):  # Windows machine?
    ...
file = infile[:-3] + '.gif'  # string slice of infile
answer = answer.lower()      # lower case
answer = answer.replace(' ', '_')
words = line.split()