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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 evaluate(self, item):
 """ Pull the field off the item """

        try:
            for match in PATH_PATTERN.finditer(self.field):
                path = match.group(0)
                if path[0] == "[":
                    # If we're selecting an item at a specific index of an
                    # array, we will usually not get back the whole array from
                    # Dynamo. It'll return an array with one element.
                    try:
                        item = item[int(match.group(1))]
                    except IndexError:
                        item = item[0]
                else:
                    item = item.get(path)
        except (IndexError, TypeError, AttributeError):
            return None
        return item