Commit 17a4322d authored by R David Murray's avatar R David Murray

#20628: wrap lines to < 80.

parent d2b5b316
...@@ -164,42 +164,43 @@ The :mod:`csv` module defines the following functions: ...@@ -164,42 +164,43 @@ The :mod:`csv` module defines the following functions:
The :mod:`csv` module defines the following classes: The :mod:`csv` module defines the following classes:
.. class:: DictReader(csvfile, fieldnames=None, restkey=None, restval=None, dialect='excel', *args, **kwds) .. class:: DictReader(csvfile, fieldnames=None, restkey=None, restval=None, \
dialect='excel', *args, **kwds)
Create an object which operates like a regular reader but maps the information Create an object which operates like a regular reader but maps the
read into a dict whose keys are given by the optional *fieldnames* information read into a dict whose keys are given by the optional
parameter. The *fieldnames* parameter is a :ref:`sequence *fieldnames* parameter. The *fieldnames* parameter is a :ref:`sequence
<collections-abstract-base-classes>` whose elements are associated with the <collections-abstract-base-classes>` whose elements are associated with the
fields of the input data in order. These elements become the keys of the fields of the input data in order. These elements become the keys of the
resulting dictionary. resulting dictionary. If the *fieldnames* parameter is omitted, the values
If the *fieldnames* parameter is omitted, the values in the first row of the in the first row of the *csvfile* will be used as the fieldnames. If the
*csvfile* will be used as the fieldnames. If the row read has more fields row read has more fields than the fieldnames sequence, the remaining data is
than the fieldnames sequence, the remaining data is added as a sequence added as a sequence keyed by the value of *restkey*. If the row read has
keyed by the value of *restkey*. If the row read has fewer fields than the fewer fields than the fieldnames sequence, the remaining keys take the value
fieldnames sequence, the remaining keys take the value of the optional of the optional *restval* parameter. Any other optional or keyword
*restval* parameter. Any other optional or keyword arguments are passed to arguments are passed to the underlying :class:`reader` instance.
the underlying :class:`reader` instance.
.. class:: DictWriter(csvfile, fieldnames, restval='', extrasaction='raise', dialect='excel', *args, **kwds) .. class:: DictWriter(csvfile, fieldnames, restval='', extrasaction='raise', \
dialect='excel', *args, **kwds)
Create an object which operates like a regular writer but maps dictionaries onto Create an object which operates like a regular writer but maps dictionaries
output rows. The *fieldnames* parameter is a :ref:`sequence onto output rows. The *fieldnames* parameter is a :ref:`sequence
<collections-abstract-base-classes>` of keys that identify the order in <collections-abstract-base-classes>` of keys that identify the order in
which values in which values in the dictionary passed to the :meth:`writerow` method are
the dictionary passed to the :meth:`writerow` method are written to the written to the *csvfile*. The optional *restval* parameter specifies the
*csvfile*. The optional *restval* parameter specifies the value to be written value to be written if the dictionary is missing a key in *fieldnames*. If
if the dictionary is missing a key in *fieldnames*. If the dictionary passed to the dictionary passed to the :meth:`writerow` method contains a key not
the :meth:`writerow` method contains a key not found in *fieldnames*, the found in *fieldnames*, the optional *extrasaction* parameter indicates what
optional *extrasaction* parameter indicates what action to take. If it is set action to take. If it is set to ``'raise'`` a :exc:`ValueError` is raised.
to ``'raise'`` a :exc:`ValueError` is raised. If it is set to ``'ignore'``, If it is set to ``'ignore'``, extra values in the dictionary are ignored.
extra values in the dictionary are ignored. Any other optional or keyword Any other optional or keyword arguments are passed to the underlying
arguments are passed to the underlying :class:`writer` instance. :class:`writer` instance.
Note that unlike the :class:`DictReader` class, the *fieldnames* parameter of Note that unlike the :class:`DictReader` class, the *fieldnames* parameter
the :class:`DictWriter` is not optional. Since Python's :class:`dict` objects of the :class:`DictWriter` is not optional. Since Python's :class:`dict`
are not ordered, there is not enough information available to deduce the order objects are not ordered, there is not enough information available to deduce
in which the row should be written to the *csvfile*. the order in which the row should be written to the *csvfile*.
.. class:: Dialect .. class:: Dialect
......
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