code: def _compute_daily_returns(g):
      return (g[-1] - g[0]) / g[0]
  
file_path: zipline/zipline/sources/benchmark_source.py
imports: import pandas
  from zipline.errors import InvalidBenchmarkAsset, BenchmarkAssetNotAvailableTooEarly, BenchmarkAssetNotAvailableTooLate
label_desc: Use image node_id 6 for calling the BenchmarkSource obj's underlying member method code with example usage: obj._compute_daily_returns(g) and returns: unknown