Python 字符串中的双括号

variable = 1

print('{}')
# output: {}

print('{{}}')
# output: {{}}

print(f'{{}}')
# output: {}

print(f'{variable}')
# output: 1

print(f'{{variable}}')
# output: {variable}

print('{}'.format(variable))
# output: 1

print('{{}}'.format(variable))
# output: {}

print('{variable}'.format(variable))
# output: error

print('{{variable}}'.format(variable))
# output: {variable}

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