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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def iterencode(self, o, _one_shot=False):
 """JSON encoder with NaN and float inf support. The sole purpose of defining a custom JSONEncoder class is to override floatstr() inner function, or more specifically the representation of NaN and +/-float('inf') values in a JSON. Although Infinity values are not supported by JSON standard, we still can convince Javascript JSON.parse() to create a Javascript Infinity object if we feed a token `1e+999` to it. """

        if self.check_circular:
            markers = {}
        else:
            markers = None

        if self.ensure_ascii:
            _encoder = encoder.encode_basestring_ascii
        else:
            _encoder = encoder.encode_basestring

        # On Python 3, JSONEncoder has no more encoding attribute, it produces
        # an Unicode string
        if six.PY2 and self.encoding != 'utf-8':
            def _encoder(o, _orig_encoder=_encoder, _encoding=self.encoding):
                if isinstance(o, str):
                    o = o.decode(_encoding)
                return _orig_encoder(o)

        def floatstr(o, allow_nan=self.allow_nan, _repr=float.__repr__,
                     _inf=encoder.INFINITY, _neginf=-encoder.INFINITY):
            # Check for specials.  Note that this type of test is processor
            # and/or platform-specific, so do tests which don't depend on the
            # internals.

            # NOTE: In Python, NaN == NaN returns False and it can be used
            # to detect NaN.
            # pylint: disable=comparison-with-itself
            if o != o:
                text = self.nan_str
            elif o == _inf:
                text = self.inf_str
            elif o == _neginf:
                text = '-' + self.inf_str
            else:
                return _repr(o)

            if not allow_nan:
                raise ValueError(
                    _("Out of range float values are not JSON compliant: %r") %
                    o)

            return text

        _iterencode = json.encoder._make_iterencode(
            markers, self.default, _encoder, self.indent, floatstr,
            self.key_separator, self.item_separator, self.sort_keys,
            self.skipkeys, _one_shot)
        return _iterencode(o, 0)