text: import pandas as pd
  
  
  class CoagmetData:
      
      def __init__(self, df=None):
          self.df = df
          
      def columns(self):
          return self.df.columns.tolist()
          
      def get(self, columns=None):
          if columns:
              return self.df[columns]
          else:
              return self.df
      
      def request(self):
          raise NotImplementedError
      
      def read_csv(self, filename, *args, **kwargs):
          self.df = pd.read_csv(filename, *args, **kwargs)
      
      def to_csv(self, filename, *args, **kwargs):
          self.df.to_csv(filename, *args, **kwargs)
  