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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 param(name, value_info, is_required=True, label=None, desc=None):
 """ Annotate a parameter of the action being defined. @param name: name of the parameter defined. @type name: unicode or str @param value_info: the parameter value information. @type value_info: value.IValueInfo @param is_required: if the parameter is required or optional. @type is_required: bool @param label: the parameter label or None. @type label: str or unicode or None @param desc: the parameter description or None. @type desc: str or unicode or None """

    _annotate("param", name, value_info, is_required=is_required,
              label=label, desc=desc)