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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 validate(self, value):
 """Validate the length of a list. :param value: List of values. :raises: :class:`halogen.exception.ValidationError` exception when length of the list is less than minimum or greater than maximum. """

        try:
            length = len(value)
        except TypeError:
            length = 0

        if self.min_length is not None:
            min_length = self.min_length() if callable(self.min_length) else self.min_length
            if length < min_length:
                raise exceptions.ValidationError(self.min_err.format(min_length))

        if self.max_length is not None:
            max_length = self.max_length() if callable(self.max_length) else self.max_length
            if length > max_length:
                raise exceptions.ValidationError(self.max_err.format(max_length))