Python Pocket Reference, 3rd Edition

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Python Pocket Reference

Attributes (all read-only)

file.closed

True

if file has been closed

file.mode

Mode string (e.g., 'r') passed to open function

file.name

String name of corresponding external file

Notes

• Some file-open modes (e.g., 'r+') allow a file to be both

input and output, and others (e.g.,

'rb') specify binary-

mode transfer to suppress line-end marker conversions.

See

open in the section “Built-in Functions,” later in this

book.

• File-transfer operations occur at the current file position,

but

seek method calls reposition the file for random

access.

• File transfers can be made unbuffered: see

open in the sec-

tion “Built-in Functions,” later in this book, and the

-u

command-line flag in the section “Command-Line

Options,” earlier in this book.

Other Common Types

As of Python 2.4, explicit Booleans, sets, and a numeric deci-

mal type are also available.

Boolean

The Boolean type, named bool, provides two predefined con-

stants, named

True and False (available since Version 2.3).

For most purposes, these constants can be treated as though

they were pre-assigned to integers 1 and 0, respectively (e.g.,

True + 3 yields 4). However, the bool type is a subclass of the

integer type,

int, and customizes it to print instances differ-

ently (

True prints as “True”, not “1”).

Specific Built-in Types

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Sets

Set ...