Python center string using format specifier

You need to centre each line separately:

'\n'.join('{:^80}'.format(s) for s in message.split('\n'))

Here is an alternative that will auto center your text based on the longest width.

def centerify(text, width=-1):
  lines = text.split('\n')
  width = max(map(len, lines)) if width == -1 else width
  return '\n'.join(line.center(width) for line in lines)

print(centerify("Hello, welcome!\nThis is some text that should be centered!"))
print(centerify("Hello, welcome!\nThis is some text that should be centered!", 80))

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