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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 create_output(self, key, value, variable_type=None):
 """Wrapper for Create method of CRUD operation for working with KeyValue DB. This method will automatically check to see if provided variable was requested by a downstream app and if so create the data in the KeyValue DB. Args: key (string):
 The variable to write to the DB. value (any):
 The data to write to the DB. variable_type (string):
 The variable type being written. Returns: (string):
 Result string of DB write. """

        results = None
        if key is not None:
            key = key.strip()
            key_type = '{}-{}'.format(key, variable_type)
            if self.out_variables_type.get(key_type) is not None:
                # variable key-type has been requested
                v = self.out_variables_type.get(key_type)
                self.tcex.log.info(
                    u'Variable {} was requested by downstream app.'.format(v.get('variable'))
                )
                if value is not None:
                    results = self.create(v.get('variable'), value)
                else:
                    self.tcex.log.info(
                        u'Variable {} has a none value and will not be written.'.format(key)
                    )
            elif self.out_variables.get(key) is not None and variable_type is None:
                # variable key has been requested
                v = self.out_variables.get(key)
                self.tcex.log.info(
                    u'Variable {} was requested by downstream app.'.format(v.get('variable'))
                )
                if value is not None:
                    results = self.create(v.get('variable'), value)
                else:
                    self.tcex.log.info(
                        u'Variable {} has a none value and will not be written.'.format(
                            v.get('variable')
                        )
                    )
            else:
                var_value = key
                if variable_type is not None:
                    var_value = key_type
                self.tcex.log.info(
                    u'Variable {} was NOT requested by downstream app.'.format(var_value)
                )
        return results