code: def test_historical_mean_return():
      orig = [13.178779135809942, 3.8135072274034982]
      l1 = np.array(range(1, 101)).astype(np.float64)
      l2 = [10 * 0.2 + i * 0.25 for i in range(21, 121)]
      d = {"1": l1, "2": l2}
      df = pd.DataFrame(d)
      ret = historical_mean_return(df, freq=252)
      assert abs(ret["1"] - orig[0]) <= 1e-15
      assert abs(ret["2"] - orig[1]) <= 1e-15
  
file_path: FinQuant/tests/test_returns.py
imports: import numpy
  import pandas
  from finquant.returns import cumulative_returns, daily_log_returns, daily_returns, historical_mean_return, weighted_mean_daily_returns
label_desc: Use image node_id 5 for calling a global function with example usage: test_historical_mean_return() without return types