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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 get_field_value(self, key, default=MISSING):
 """Method to fetch a value from either the fields metadata or the schemas context, in that order. Args: key (str):
 The name of the key to grab the value for. Keyword Args: default (object, optional):
 If the value doesn't exist in the schema's ``context`` or the field's ``metadata``, this value will be returned. By default this will be ``MISSING``. Returns: object: This will be the correct value to use given the parameters. """

        meta_value = self.metadata.get(key)
        context_value = self.context.get(key)

        if context_value is not None:
            return context_value
        elif meta_value is not None:
            return meta_value

        return default