class_docstr: Tracks the performance of the algorithm.
code: def get_account(self, performance_needs_update):
      if performance_needs_update:
          self.update_performance()
          self.account_needs_update = True
      if self.account_needs_update:
          self._update_account()
      return self._account
  
imports: from __future__ import division
  import logbook
  import pandas
  from pandas.tseries.tools import normalize_date
  from catalyst.finance.performance.period import PerformancePeriod
  from catalyst.errors import NoFurtherDataError
  import catalyst.finance.risk
  from .position_tracker import PositionTracker
  from catalyst.constants import LOG_LEVEL
label_desc: Use image node_id 7 for calling the PerformanceTracker obj's underlying member method code with example usage: obj.get_account(performance_needs_update) and returns: self