def is_firstline(text, medicine, disease):
  """Detect if first-line treatment is mentioned with a medicine in a sentence.

  Use keyword matching to detect if the keywords "first-line treatment" or "first-or second-line treatment", medicine name, and disease name all appear in the sentence.

  Parameters
  ----------
  text : str
      A single sentence.
  medicine : str
      A medicine's name.

  Returns
  -------
  bool
      Return True if the medicine and first-line treatment are mentioned in the sentence, False otherwise. 
  
  Examples
  --------
  Import the module

  >>> from biomarker_nlp import biomarker_extraction
  
  Example
  
  >>> txt = "TECENTRIQ, in combination with carboplatin and etoposide, is indicated for the first-line treatment of adult patients with extensive-stage small cell lung cancer (ES-SCLC)."
  >>> medicine = "TECENTRIQ"
  >>> disease = "small cell lung cancer"
  >>> biomarker_extraction.is_firstline(text = txt, medicine = medicine, disease = disease)
  True

  """
  text = text.lower()
  medicine = medicine.lower()
  disease = disease.lower()
  if medicine in text and ('first-line treatment' in text or 'first-or second-line treatment' in text) and disease in text:
    return True
  else:
    return False