def __init__(self, name, dtype, defVal=None, virtualOnly=False):
self.name = name<EOL>self._dtype = dtype<EOL>self.virtualOnly = virtualOnly<EOL>if defVal is None:<EOL><INDENT>defVal = dtype.fromPy(None)<EOL><DEDENT>self.defVal = defVal<EOL>self._setDefValue()<EOL>
:param name: name for better orientation in netlists
    (used only in serialization)
:param dtype: data type of this signal
:param defVal: value for initialization
:param virtualOnly: flag indicates that this assignments is only
    virtual and should not be added into
    netlist, because it is only for internal notation