def _CombineBitloading(bitlines):
  """Combine bitloading information into one string.

  Args:
    bitlines: a list of lines of bitloading info:
    00008888888888888888888888888888     00008888888888888888888888888888
    88888888888888888888888888888888     88888888888888888888888888888888
    88888888888888888888888888888888     88888888888888888888888888888888
    88888888888888888888000000000000     88888888888888888888000000000000
    00000000000008888888888888888888     00000000000008888888888888888888
    88888888888888888888888888888888     88888888888888888888888888888888
    88888888888888888888888888888888     88888888888888888888888888888888
    88888888888888888888888888888000     88888888888888888888888888888000

  Returns:
    a tuple of two contiguous strings, '00008888888...888888000',
    for the left-hand and right-hand bitloading.
  """

  left = []
  right = []
  for line in bitlines:
    (l, r) = line.split()
    left.append(l.strip())
    right.append(r.strip())
  return (''.join(left), ''.join(right))