def lines_in(file_like):
  """Enumerate lines in a stream.

  Call file_like's iterator method and iterate over that.  Will
  skip any lines starting with # and blank lines.

  Args:
    file_like: An iterator over lines.

  Yields:
    a string for each line in the file or stream.
  """
  for line in file_like:
    if line[0] != '#' and line != '\n':
      yield line
Enumerate lines in a stream.

  Call file_like's iterator method and iterate over that.  Will
  skip any lines starting with # and blank lines.

  Args:
    file_like: An iterator over lines.

  Yields:
    a string for each line in the file or stream.
  
language/nql/nql/io.py