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Module: nbformat.v3.nbjson

Inheritance diagram for IPython.nbformat.v3.nbjson:

Read and write notebooks in JSON format.


  • Brian Granger



class IPython.nbformat.v3.nbjson.BytesEncoder(skipkeys=False, ensure_ascii=True, check_circular=True, allow_nan=True, sort_keys=False, indent=None, separators=None, encoding='utf-8', default=None)

Bases: json.encoder.JSONEncoder

A JSON encoder that accepts b64 (and other ascii) bytestrings.

__init__(skipkeys=False, ensure_ascii=True, check_circular=True, allow_nan=True, sort_keys=False, indent=None, separators=None, encoding='utf-8', default=None)

Constructor for JSONEncoder, with sensible defaults.

If skipkeys is false, then it is a TypeError to attempt encoding of keys that are not str, int, long, float or None. If skipkeys is True, such items are simply skipped.

If ensure_ascii is true, the output is guaranteed to be str objects with all incoming unicode characters escaped. If ensure_ascii is false, the output will be unicode object.

If check_circular is true, then lists, dicts, and custom encoded objects will be checked for circular references during encoding to prevent an infinite recursion (which would cause an OverflowError). Otherwise, no such check takes place.

If allow_nan is true, then NaN, Infinity, and -Infinity will be encoded as such. This behavior is not JSON specification compliant, but is consistent with most JavaScript based encoders and decoders. Otherwise, it will be a ValueError to encode such floats.

If sort_keys is true, then the output of dictionaries will be sorted by key; this is useful for regression tests to ensure that JSON serializations can be compared on a day-to-day basis.

If indent is a non-negative integer, then JSON array elements and object members will be pretty-printed with that indent level. An indent level of 0 will only insert newlines. None is the most compact representation.

If specified, separators should be a (item_separator, key_separator) tuple. The default is (‘, ‘, ‘: ‘). To get the most compact JSON representation you should specify (‘,’, ‘:’) to eliminate whitespace.

If specified, default is a function that gets called for objects that can’t otherwise be serialized. It should return a JSON encodable version of the object or raise a TypeError.

If encoding is not None, then all input strings will be transformed into unicode using that encoding prior to JSON-encoding. The default is UTF-8.


Return a JSON string representation of a Python data structure.

>>> JSONEncoder().encode({"foo": ["bar", "baz"]})
'{"foo": ["bar", "baz"]}'
item_separator = ', '
iterencode(o, _one_shot=False)

Encode the given object and yield each string representation as available.

For example:

for chunk in JSONEncoder().iterencode(bigobject):
key_separator = ': '


class IPython.nbformat.v3.nbjson.JSONReader

Bases: IPython.nbformat.v3.rwbase.NotebookReader


x.__init__(...) initializes x; see help(type(x)) for signature

read(fp, **kwargs)

Read a notebook from a file like object

reads(s, **kwargs)
to_notebook(d, **kwargs)


class IPython.nbformat.v3.nbjson.JSONWriter

Bases: IPython.nbformat.v3.rwbase.NotebookWriter


x.__init__(...) initializes x; see help(type(x)) for signature

write(nb, fp, **kwargs)

Write a notebook to a file like object

writes(nb, **kwargs)