code: def get_sharpe_ratio_from_return_series(
      r, risk_free_rate=0.00, method="ci"
  ):
      """Risk Analysis
  
      Parameters
      ----------
      r : pandas.Series
          daily return series
      method : str
          interest calculation method, ci(compound interest)/si(simple interest)
      risk_free_rate : float
          risk_free_rate, default as 0.00, can set as 0.03 etc
      """
      std = r.std(ddof=1)
      annual = get_annaul_return_from_return_series(r, method=method)
      sharpe = (annual - risk_free_rate) / std / np.sqrt(250)
  
      return sharpe
  
imports: from __future__ import division
  from __future__ import print_function
  import numpy
  import pandas
  from scipy.stats import spearmanr, pearsonr
  from ..data import D
  from collections import OrderedDict
label_desc: Use image node_id 7 for calling a global function with example usage: get_sharpe_ratio_from_return_series(r, risk_free_rate, method) and returns: sharpe