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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 toJson(self, data=None, pretty=False):
 """convert the flattened dictionary into json"""

        if data==None: data = self.attrs
        data = self.flatten(data) # don't send objects as str in json
        #if pretty:
        ret = json.dumps(data, indent=4, sort_keys=True)
        #self.inflate() # restore objects from json str data
        return ret