def encode(self, o):
        """Return a JSON string representation of a Python data structure.

        >>> JSONEncoder().encode({"foo": ["bar", "baz"]})
        '{"foo": ["bar", "baz"]}'

        """
        # This is for extremely simple cases and benchmarks.
        if isinstance(o, basestring):
            if isinstance(o, str):
                _encoding = self.encoding
                if (_encoding is not None
                        and not (_encoding == 'utf-8')):
                    o = o.decode(_encoding)
            if self.ensure_ascii:
                return encode_basestring_ascii(o)
            else:
                return encode_basestring(o)
        # This doesn't pass the iterator directly to ''.join() because the
        # exceptions aren't as detailed.  The list call should be roughly
        # equivalent to the PySequence_Fast that ''.join() would do.
        chunks = self.iterencode(o, _one_shot=True)
        if not isinstance(chunks, (list, tuple)):
            chunks = list(chunks)
        return ''.join(chunks)
Return a JSON string representation of a Python data structure.

        >>> JSONEncoder().encode({"foo": ["bar", "baz"]})
        '{"foo": ["bar", "baz"]}'

        
mapreduce/lib/simplejson/encoder.py