def argflag(key, argv=None):
if argv is None:  <EOL><INDENT>argv = sys.argv<EOL><DEDENT>keys = [key] if isinstance(key, six.string_types) else key<EOL>flag = any(k in argv for k in keys)<EOL>return flag<EOL>
Determines if a key is specified on the command line

Args:
    key (str or tuple): string or tuple of strings. Each key should be
        prefixed with two hyphens (i.e. `--`)
    argv (Optional[list]): overrides `sys.argv` if specified

Returns:
    bool: flag : True if the key (or any of the keys) was specified

Example:
    >>> import ubelt as ub
    >>> argv = ['--spam', '--eggs', 'foo']
    >>> assert ub.argflag('--eggs', argv=argv) is True
    >>> assert ub.argflag('--ans', argv=argv) is False
    >>> assert ub.argflag('foo', argv=argv) is True
    >>> assert ub.argflag(('bar', '--spam'), argv=argv) is True