son – Tools for working with SON, an ordered mapping¶
Tools for creating and manipulating SON, the Serialized Ocument Notation.
Regular dictionaries can be used instead of SON objects, but not when the order of keys is important. A SON object can be used just like a normal Python dictionary.
A subclass of dict that maintains ordering of keys and provides a few extra niceties for dealing with SON. SON objects can be converted to and from BSON.
The mapping from Python types to BSON types is as follows:
Python Type BSON Type Supported Direction None null both bool boolean both int  int32 / int64 py -> bson long int64 py -> bson bson.int64.Int64 int64 both float number (real) both string string py -> bson unicode string both list array both dict / SON object both datetime.datetime   date both bson.regex.Regex regex both compiled re  regex py -> bson bson.binary.Binary binary both bson.objectid.ObjectId oid both bson.dbref.DBRef dbref both None undefined bson -> py unicode code bson -> py bson.code.Code code py -> bson unicode symbol bson -> py bytes (Python 3)  binary both
Note that to save binary data it must be wrapped as an instance of bson.binary.Binary. Otherwise it will be saved as a BSON string and retrieved as unicode.
 A Python int will be saved as a BSON int32 or BSON int64 depending on its size. A BSON int32 will always decode to a Python int. A BSON int64 will always decode to a
 datetime.datetime instances will be rounded to the nearest millisecond when saved  all datetime.datetime instances are treated as naive. clients should always use UTC. 
Regexinstances and regular expression objects from
re.compile()are both saved as BSON regular expressions. BSON regular expressions are decoded as
 The bytes type from Python 3.x is encoded as BSON binary with subtype 0. In Python 3.x it will be decoded back to bytes. In Python 2.x it will be decoded to an instance of
Binarywith subtype 0.
Convert a SON document to a normal Python dictionary instance.
This is trickier than just dict(...) because it needs to be recursive.