Python JSON serialize a Decimal object

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I would like to let everyone know that I tried Michał Marczyk’s answer on my web server that was running Python 2.6.5 and it worked fine. However, I upgraded to Python 2.7 and it stopped working. I tried to think of some sort of way to encode Decimal objects and this is what I came up with:

import decimal

class DecimalEncoder(json.JSONEncoder):
    def default(self, o):
        if isinstance(o, decimal.Decimal):
            return str(o)
        return super(DecimalEncoder, self).default(o)

Note that this will convert the decimal to its string representation (e.g.; "1.2300") to a. not lose significant digits and b. prevent rounding errors.

This should hopefully help anyone who is having problems with Python 2.7. I tested it and it seems to work fine. If anyone notices any bugs in my solution or comes up with a better way, please let me know.

Usage example:

json.dumps({'x': decimal.Decimal('5.5')}, cls=DecimalEncoder)

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