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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 parse(self, text, layers=None):
 """Parsing passed text to json. Args: text: Text to parse. layers (optional):
 Special fields. Only one string or iterable object (e.g "Data", ("Data", "Fio")). Only these fields will be returned. Returns: The parsed text into a json object. """

        params = {
            "text": text,
            "key": self.key,
        }

        if layers is not None:
            # if it's string
            if isinstance(layers, six.string_types):
                params["layers"] = layers

            # if it's another iterable object
            elif isinstance(layers, collections.Iterable):
                params["layers"] = ",".join(layers)

        req = requests.get(self.NLU_URL, params=params)
        return req.json()