def extract_column(col_num, table):
    """
    Extract a list representing a column from 2
    dimensional list
    INPUTS:
    col_num - determines which item in the row will be
              extracted
    table -   2 dimensional list. Each inner list represents
              one 1 row in the table
    """
    column = []
    for row in table:
        if len(row) - 1 >= col_num:
            column.append(str(row[col_num]))
    return column