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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 open_grindstone(self):
 """ Opens a grindstone file and populates the grindstone with it's contents. Returns an empty grindstone json object if a file does not exist. """

        try:
            with open(self.grindstone_path, 'r') as f:
                # Try opening the file
                return json.loads(f.read())
        # If the file is empty
        except json.decoder.JSONDecodeError:
            # Default return empty object with empty tasks list
            return {'tasks': []}
        # The file does not yet exist
        except FileNotFoundError:
            # Default return empty object with empty tasks list
            return {'tasks': []}