class_docstr: A SQLiteAdjustmentReader that stores no adjustments and uses in-memory
  SQLite.
code: def __init__(self):
      conn = sqlite3_connect(":memory:")
      writer = SQLiteAdjustmentWriter(conn, None, None)
      empty = DataFrame(
          {
              "sid": array([], dtype=uint32),
              "effective_date": array([], dtype=uint32),
              "ratio": array([], dtype=float),
          }
      )
      empty_dividends = DataFrame(
          {
              "sid": array([], dtype=uint32),
              "amount": array([], dtype=float64),
              "record_date": array([], dtype="datetime64[ns]"),
              "ex_date": array([], dtype="datetime64[ns]"),
              "declared_date": array([], dtype="datetime64[ns]"),
              "pay_date": array([], dtype="datetime64[ns]"),
          }
      )
      writer.write(
          splits=empty, mergers=empty, dividends=empty_dividends
      )
      super(NullAdjustmentReader, self).__init__(conn)
  
imports: from numpy import arange, array, eye, float64, full, iinfo, uint32
  from numpy.random import RandomState
  from pandas import DataFrame, Timestamp
  from six import iteritems
  from sqlite3 import connect
  from .base import PipelineLoader
  from .frame import DataFrameLoader
  from catalyst.data.us_equity_pricing import SQLiteAdjustmentReader, SQLiteAdjustmentWriter, US_EQUITY_PRICING_BCOLZ_COLUMNS
  from catalyst.utils.numpy_utils import bool_dtype, datetime64ns_dtype, float64_dtype, int64_dtype, object_dtype
label_desc: Use image node_id 1 to create a new NullAdjustmentReader object from inherited base classes: SQLiteAdjustmentReader with example: obj = NullAdjustmentReader()