def split_args(args):
    """
    Split a list of argument strings into a dictionary where each key is an
    argument name.

    An argument looks like ``crop``, ``crop="some option"`` or ``crop=my_var``.
    Arguments which provide no value get a value of ``True``.

    """
    args_dict = {}
    for arg in args:
        split_arg = arg.split('=', 1)
        if len(split_arg) > 1:
            value = split_arg[1]
        else:
            value = True
        args_dict[split_arg[0]] = value
    return args_dict