text: #
  # Copyright 2013 Quantopian, Inc.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  
  import pytz
  import numbers
  
  from hashlib import md5
  from datetime import datetime
  from zipline.protocol import DATASOURCE_TYPE
  
  
  def hash_args(*args, **kwargs):
      """Define a unique string for any set of representable args."""
      arg_string = "_".join([str(arg) for arg in args])
      kwarg_string = "_".join(
          [str(key) + "=" + str(value) for key, value in kwargs.items()]
      )
      combined = ":".join([arg_string, kwarg_string])
  
      hasher = md5()
      hasher.update(combined)
      return hasher.hexdigest()
  
  
  def assert_datasource_protocol(event):
      """Assert that an event meets the protocol for datasource outputs."""
  
      assert event.type in DATASOURCE_TYPE
  
      # Done packets have no dt.
      if not event.type == DATASOURCE_TYPE.DONE:
          assert isinstance(event.dt, datetime)
          assert event.dt.tzinfo == pytz.utc
  
  
  def assert_trade_protocol(event):
      """Assert that an event meets the protocol for datasource TRADE outputs."""
      assert_datasource_protocol(event)
  
      assert event.type == DATASOURCE_TYPE.TRADE
      assert isinstance(event.price, numbers.Real)
      assert isinstance(event.volume, numbers.Integral)
      assert isinstance(event.dt, datetime)
  
  
  def assert_datasource_unframe_protocol(event):
      """Assert that an event is valid output of zp.DATASOURCE_UNFRAME."""
      assert event.type in DATASOURCE_TYPE
  