docs: def rnd_date_array(self, size, start=date(1970, 1, 1), end=date.today()):
          """Array or Matrix of random date generator.
          """
          if isinstance(start, string_types):
              start = self.str2date(start)
          if isinstance(end, string_types):
              end = self.str2date(end)
          if start > end:
              raise ValueError("start time has to be earlier than end time")
  
          return self.randn(size, self._rnd_date, start, end)