Merge with 3.2.
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32657fb152
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@ -40,8 +40,8 @@ which can be read by the interpreter (or will force a :exc:`SyntaxError` if
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there is not equivalent syntax). For objects which don't have a particular
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representation for human consumption, :func:`str` will return the same value as
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:func:`repr`. Many values, such as numbers or structures like lists and
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dictionaries, have the same representation using either function. Strings and
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floating point numbers, in particular, have two distinct representations.
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dictionaries, have the same representation using either function. Strings, in
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particular, have two distinct representations.
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Some examples::
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@ -50,9 +50,7 @@ Some examples::
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'Hello, world.'
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>>> repr(s)
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"'Hello, world.'"
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>>> str(1.0/7.0)
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'0.142857142857'
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>>> repr(1.0/7.0)
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>>> str(1/7)
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'0.14285714285714285'
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>>> x = 10 * 3.25
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>>> y = 200 * 200
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@ -103,17 +101,18 @@ Here are two ways to write a table of squares and cubes::
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(Note that in the first example, one space between each column was added by the
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way :func:`print` works: it always adds spaces between its arguments.)
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This example demonstrates the :meth:`rjust` method of string objects, which
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right-justifies a string in a field of a given width by padding it with spaces
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on the left. There are similar methods :meth:`ljust` and :meth:`center`. These
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methods do not write anything, they just return a new string. If the input
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string is too long, they don't truncate it, but return it unchanged; this will
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mess up your column lay-out but that's usually better than the alternative,
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which would be lying about a value. (If you really want truncation you can
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always add a slice operation, as in ``x.ljust(n)[:n]``.)
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This example demonstrates the :meth:`str.rjust` method of string
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objects, which right-justifies a string in a field of a given width by padding
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it with spaces on the left. There are similar methods :meth:`str.ljust` and
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:meth:`str.center`. These methods do not write anything, they just return a
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new string. If the input string is too long, they don't truncate it, but
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return it unchanged; this will mess up your column lay-out but that's usually
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better than the alternative, which would be lying about a value. (If you
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really want truncation you can always add a slice operation, as in
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``x.ljust(n)[:n]``.)
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There is another method, :meth:`zfill`, which pads a numeric string on the left
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with zeros. It understands about plus and minus signs::
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There is another method, :meth:`str.zfill`, which pads a numeric string on the
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left with zeros. It understands about plus and minus signs::
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>>> '12'.zfill(5)
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'00012'
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@ -128,16 +127,16 @@ Basic usage of the :meth:`str.format` method looks like this::
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We are the knights who say "Ni!"
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The brackets and characters within them (called format fields) are replaced with
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the objects passed into the :meth:`~str.format` method. A number in the
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the objects passed into the :meth:`str.format` method. A number in the
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brackets can be used to refer to the position of the object passed into the
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:meth:`~str.format` method. ::
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:meth:`str.format` method. ::
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>>> print('{0} and {1}'.format('spam', 'eggs'))
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spam and eggs
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>>> print('{1} and {0}'.format('spam', 'eggs'))
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eggs and spam
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If keyword arguments are used in the :meth:`~str.format` method, their values
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If keyword arguments are used in the :meth:`str.format` method, their values
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are referred to by using the name of the argument. ::
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>>> print('This {food} is {adjective}.'.format(
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@ -195,8 +194,8 @@ notation. ::
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>>> print('Jack: {Jack:d}; Sjoerd: {Sjoerd:d}; Dcab: {Dcab:d}'.format(**table))
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Jack: 4098; Sjoerd: 4127; Dcab: 8637678
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This is particularly useful in combination with the new built-in :func:`vars`
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function, which returns a dictionary containing all local variables.
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This is particularly useful in combination with the built-in function
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:func:`vars`, which returns a dictionary containing all local variables.
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For a complete overview of string formatting with :meth:`str.format`, see
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:ref:`formatstrings`.
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