code: def unix_timestamp_to_datetime(unix_timestamp):
    
  
    # Is 'unix_timestamp' properly formatted?
    # Raise 'securesystemslib.exceptions.FormatError' if there is a mismatch.
    securesystemslib.formats.UNIX_TIMESTAMP_SCHEMA.check_match(unix_timestamp)
  
    # Convert 'unix_timestamp' to a 'time.struct_time',  in UTC.  The Daylight
    # Savings Time (DST) flag is set to zero.  datetime.fromtimestamp() is not
    # used because it returns a local datetime.
    struct_time = time.gmtime(unix_timestamp)
  
    # Extract the (year, month, day, hour, minutes, seconds) arguments for the
    # datetime object to be returned.
    datetime_object = datetime.datetime(*struct_time[:6])
  
    return datetime_object
docs: <Purpose>
      Convert 'unix_timestamp' (i.e., POSIX time, in UNIX_TIMESTAMP_SCHEMA format)
      to a datetime.datetime() object.  'unix_timestamp' is the number of seconds
      since the epoch (January 1, 1970.)
  
      >>> datetime_object = unix_timestamp_to_datetime(1445455680)
      >>> datetime_object
      datetime.datetime(2015, 10, 21, 19, 28)
  
    <Arguments>
      unix_timestamp:
        An integer representing the time (e.g., 1445455680).  Conformant to
        'securesystemslib.formats.UNIX_TIMESTAMP_SCHEMA'.
  
    <Exceptions>
      securesystemslib.exceptions.FormatError, if 'unix_timestamp' is improperly
      formatted.
  
    <Side Effects>
      None.
  
    <Returns>
      A datetime.datetime() object corresponding to 'unix_timestamp'.