def screen(row, col, maxwell, **kwargs):
    """
    Create a screen with global parameters

    Parameters
    ----------
    row : string
        Parameter encoded by the row letter
    col : string
        Parameter encoded by the column number
    maxwell : string
        Name of the well in the bottom-right corner of each tray, e.g. 'H6'
    **kwargs : any type
        Any named arguments become global parameters to be applied to all wells in all trays in the screen

    Returns
    -------
    screen : dict
        A dictionary containing the screen

    """
    # make sure maxwell is properly formatted
    if len(maxwell) != 2:
        raise ValueError(f'maxwell must have length 2, supplied {maxwell} has length {len(maxwell)}')
    elif not maxwell[0].isalpha():
        raise ValueError(f'first character of maxwell must be a letter, supplied {maxwell} has first character {maxwell[0]}')
    elif not maxwell[1].isdigit():
        raise ValueError(f'second character of maxwell must be a number, supplied {maxwell} has second character {maxwell[1]}')


    screen = {"row": row, "col": col, "maxwell": maxwell}

    screen["statics"] = {}

    for key, value in kwargs.items():
        screen["statics"][key] = value

    return screen