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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 _GetDaysPerMonth(self, year, month):
 """Retrieves the number of days in a month of a specific year. Args: year (int):
 year e.g. 1970. month (int):
 month, where 1 represents January. Returns: int: number of days in the month. Raises: ValueError: if the month value is out of bounds. """

    if month not in range(1, 13):
      raise ValueError('Month value out of bounds.')

    days_per_month = self._DAYS_PER_MONTH[month - 1]
    if month == 2 and self._IsLeapYear(year):
      days_per_month += 1

    return days_per_month