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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 validate(self, ymldata=None, messages=None):
 """Validates the Telemetry Dictionary definitions"""

        schema_val = self.schema_val(messages)
        if len(messages) == 0:
            content_val = self.content_val(ymldata, messages)

        return schema_val and content_val