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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 days_since_last_snowfall(self, value=99):
 """Corresponds to IDD Field `days_since_last_snowfall` Args: value (int):
 value for IDD Field `days_since_last_snowfall` Missing value: 99 if `value` is None it will not be checked against the specification and is assumed to be a missing value Raises: ValueError: if `value` is not a valid value """

        if value is not None:
            try:
                value = int(value)
            except ValueError:
                raise ValueError(
                    'value {} need to be of type int '
                    'for field `days_since_last_snowfall`'.format(value))

        self._days_since_last_snowfall = value