code: def get_epoch_price_divisor( block_height, namespace_id, units ):
      
      try:
          assert units in [TOKEN_TYPE_STACKS, 'BTC'], 'Unknown units {}'.format(units)
      except AssertionError as ae:
          log.exception(ae)
          log.error("FATAL: No such units {}".format(units))
          os.abort()
  
      divisor = 'PRICE_DIVISOR' if units == 'BTC' else 'PRICE_DIVISOR_STACKS'
  
      epoch_config = get_epoch_config( block_height )
      d = None
  
      if epoch_config['namespaces'].has_key(namespace_id):
          d = epoch_config['namespaces'][namespace_id][divisor]
      else:
          d = epoch_config['namespaces']['*'][divisor]
  
      try:
          assert d is not None
      except AssertionError as ae:
          log.exception(ae)
          log.error("FATAL: Tried to get a price divisor in an epoch without price divisors!")
          os.abort()
  
      return d
docs: what's the name price divisor for this epoch?
      Not all epochs have one---if this epoch does NOT have BLOCKSTACK_INT_DIVISION set,
      use get_epoch_price_multiplier() instead.