def decodeValue(self, value):
        # Note: value always is 1-char string
        if value == "?":
            return -1
        if value in "NnFf ":
            return False
        if value in "YyTt":
            return True
        raise ValueError("[%s] Invalid logical value %r" % (self.name, value))
Return True, False or -1 decoded from ``value``.
dataset/ETHPy150Open kennethreitz/tablib/tablib/packages/dbfpy3/fields.py/DbfLogicalFieldDef.decodeValue