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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def validate_schema(sconf):
 """ Return True if config schema is correct. Parameters sconf : dict session configuration Returns ------- bool """


    # verify session_name
    if 'session_name' not in sconf:
        raise exc.ConfigError('config requires "session_name"')

    if 'windows' not in sconf:
        raise exc.ConfigError('config requires list of "windows"')

    for window in sconf['windows']:
        if 'window_name' not in window:
            raise exc.ConfigError('config window is missing "window_name"')

        if 'panes' not in window:
            raise exc.ConfigError(
                'config window %s requires list of panes' % window['window_name']
            )

    return True