code: def get_metadata():
      
      dt = pd.read_table(ATTRACT_METADTA)
      dt.rename(columns={"Matrix_id": "PWM_id"}, inplace=True)
      # put to firt place
      cols = ['PWM_id'] + [col for col in dt if col != 'PWM_id']
  
      # rename Matrix_id to PWM_id
      return dt[cols]
docs: Get pandas.DataFrame with metadata about the Attract PWM's. Columns:
  
      - PWM_id (id of the PWM - pass to get_pwm_list() for getting the pwm
      - Gene_name
      - Gene_id
      - Mutated	(if the target gene is mutated)
      - Organism
      - Motif     (concsensus motif)
      - Len	(lenght of the motif)
      - Experiment_description(when available)
      - Database (Database from where the motifs were extracted PDB: Protein data bank, C: Cisbp-RNA, R:RBPDB, S: Spliceaid-F, AEDB:ASD)
      - Pubmed (pubmed ID)
      - Experiment (type of experiment; short description)
      - Family (domain)
      - Score (Qscore refer to the paper)