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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 _resolve_value(self, value, environment=None):
 """Resolve the value. Either apply missing or leave the value as is. :param value: the value either from deserialize or serialize :param environment: an optional environment """


        # here we care about Undefined values
        if value == values.Undefined:
            if isinstance(self._missing, type) and issubclass(self._missing, Missing):
                # instantiate the missing thing
                missing = self._missing(self, environment)

                # invoke missing callback
                # the default is to raise a MissingValue() exception
                value = missing(value)

            elif hasattr(self._missing, "__call__"):
                value = self._missing()

            else:
                # we just assign any value
                value = self._missing

        return value