code: 
  import pandas as pd
  
  
  def read_csv_files(file_path):
      return pd.read_csv(file_path)
  
  
  def filter_films(dataframe):
      pass
  
  
  def join_categories_with_metadata(facts_df, categories_df):
      # Hint: You can use lambda functions to change the id column in order to
      # use join method in pandas.
      pass
  
  
  def categories_into_one_single_column(categories_df):
      # Hint: When you use dataframe.idxmax(axis=1) you automatically
      # create a pd.Series with categorical values as strings.
      pass
  
  
  def take_year_from_movie_title_string(movie_title_str):
      try:
          pass
      except (IndexError, ValueError):
          return 9999
  
  
  def genre_count_table_for_movies_with_aggregation(categories_df):
      pass
  
  
  def calculate_ratio_of_nomination_over_win(dataframe):
      # Hint 1: Use an additional function for handling
      # zero division error.
      # Hint 2: Nominations + Wins = Total Number of Nominations
  
      pass
  
apis: pandas.read_csv