SUFFIXES = {1000: ['KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'],

1024: ['KiB', 'MiB', 'GiB', 'TiB', 'PiB', 'EiB', 'ZiB', 'YiB']}

def approximate_size(size, a_kilobyte_is_1024_bytes=True):

'''Convert a file size to human-readable form.

Keyword arguments:

size -- file size in bytes

a_kilobyte_is_1024_bytes -- if True (default), use multiples of 1024

if False, use multiples of 1000

Returns: string

'''

if size < 0:

raise ValueError('number must be non-negative')

multiple = 1024 if a_kilobyte_is_1024_bytes else 1000

for suffix in SUFFIXES[multiple]:

size /= multiple

if size < multiple:

return '{0:.1f} {1}'.format(size, suffix)

raise ValueError('number too large')

if __name__ == '__main__':

print(approximate_size(1000000000000, False))

print(approximate_size(1000000000000))

print(__name__)

# print(approximate_size(-0.2))