def join_positions(pos1, pos2):
    """Merge two positions and return as a list of strings

    pos1: iterable object containing the first positions data
    pos2: iterable object containing the second positions data

    Example:
        >>> join_positions('ABCD','1234')
            ['A1', 'B2', 'C3', 'D4']
    """
    return ["".join([r1, r2]) for r1, r2 in zip(pos1, pos2)]