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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 serialize_to_string(self, name, datas):
 """ Serialize given datas to a string. Simply return the value from required variable``value``. Arguments: name (string):
 Name only used inside possible exception message. datas (dict):
 Datas to serialize. Returns: string: Value. """

        value = datas.get('value', None)

        if value is None:
            msg = ("String reference '{}' lacks of required 'value' variable "
                   "or is empty")
            raise SerializerError(msg.format(name))

        return value