code: def calculate_unary(self, data: pd.Series) -> pd.Series:
      value_counts = data.value_counts(normalize=True)
      return self._loc(data, value_counts)
  
imports: from upgini.autofe.operand import PandasOperand
  import numpy
  import pandas
label_desc: Use image node_id 1 for calling the Freq obj's underlying member method code with example usage: obj.calculate_unary(data) and returns: self