<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def mkdir(directory, exists_okay):
 """ Create a directory on the board. Mkdir will create the specified directory on the board. One argument is required, the full path of the directory to create. Note that you cannot recursively create a hierarchy of directories with one mkdir command, instead you must create each parent directory with separate mkdir command calls. For example to make a directory under the root called 'code': ampy --port /board/serial/port mkdir /code """

    # Run the mkdir command.
    board_files = files.Files(_board)
    board_files.mkdir(directory, exists_okay=exists_okay)