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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def ReadLsbBytes(rd, offset, value_size):
 """Reads value_size bytes from rd at offset, least signifcant byte first."""


  encoding = None
  if value_size == 1:
    encoding = '<B'
  elif value_size == 2:
    encoding = '<H'
  elif value_size == 4:
    encoding = '<L'
  else:
    raise errors.HidError('Invalid value size specified')

  ret, = struct.unpack(encoding, rd[offset:offset + value_size])
  return ret