docs: def get_column_names_from_file(file_path):
          """returns column names from CTD download file
  
          :param str file_path: path to CTD download file
          """
          if file_path.endswith('.gz'):
              file_handler = io.TextIOWrapper(io.BufferedReader(gzip.open(file_path)))
          else:
              file_handler = open(file_path, 'r')
  
          fields_line = False
          with file_handler as file:
              for line in file:
                  line = line.strip()
                  if not fields_line and re.search('#\s*Fields\s*:$', line):
                      fields_line = True
                  elif fields_line and not (line == '' or line == '#'):
                      return [column.strip() for column in line[1:].split("\t")]