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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 generate_content_media_type(self):
 """ Means loading value when it's specified as JSON. .. code-block:: python { 'contentMediaType': 'application/json', } """

        if self._definition['contentMediaType'] == 'application/json':
            with self.l('if isinstance({variable}, bytes):'):
                with self.l('try:'):
                    self.l('{variable} = {variable}.decode("utf-8")')
                with self.l('except Exception:'):
                    self.l('raise JsonSchemaException("{name} must encoded by utf8")')
            with self.l('if isinstance({variable}, str):'):
                with self.l('try:'):
                    self.l('import json')
                    self.l('{variable} = json.loads({variable})')
                with self.l('except Exception:'):
                    self.l('raise JsonSchemaException("{name} must be valid JSON")')