old_contents: from tsserver import db
  from tsserver.dtutils import datetime_to_str
  
  
  class Telemetry(db.Model):
      """
      All the data that is going to be obtained in regular time intervals
      (every second or so).
      """
  
      timestamp = db.Column(db.DateTime, primary_key=True)
      temperature = db.Column(db.Float)
      """Temperature in Celsius."""
      pressure = db.Column(db.Float)
      """Air pressure in hPa."""
  
      def __init__(self, timestamp, temperature, pressure):
          self.timestamp = timestamp
          self.temperature = temperature
          self.pressure = pressure
  
      def as_dict(self):
          return {'timestamp': datetime_to_str(self.timestamp),
                  'temperature': self.temperature,
                  'pressure': self.pressure}
  
new_contents: from tsserver import db
  from tsserver.dtutils import datetime_to_str
  
  
  class Telemetry(db.Model):
      """
      All the data that is going to be obtained in regular time intervals
      (every second or so).
      """
  
      timestamp = db.Column(db.DateTime, primary_key=True)
      temperature = db.Column(db.Float)
      """Temperature in Celsius."""
      pressure = db.Column(db.Float)
      """Air pressure in hPa."""
  
      def as_dict(self):
          return {'timestamp': datetime_to_str(self.timestamp),
                  'temperature': self.temperature,
                  'pressure': self.pressure}
  
subject: Remove Telemetry.__init__ as not necessary