def get_family_name_from(seq_name_and_family):
  """Get family accession from concatenated sequence name and family string.

  Args:
    seq_name_and_family: string. Of the form `sequence_name`_`family_accession`,
      like OLF1_CHICK/41-290_PF00001.20. Assumes the family does not have an
      underscore.

  Returns:
    string. PFam family accession.
  """
  return seq_name_and_family.split('_')[-1]