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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 _calculateLrcString(inputstring):
 """Calculate LRC for Modbus. Args: inputstring (str):
 An arbitrary-length message (without the beginning colon and terminating CRLF). It should already be decoded from hex-string. Returns: A one-byte LRC bytestring (not encoded to hex-string) Algorithm from the document 'MODBUS over serial line specification and implementation guide V1.02'. The LRC is calculated as 8 bits (one byte). For example a LRC 0110 0001 (bin) = 61 (hex) = 97 (dec) = 'a'. This function will then return 'a'. In Modbus ASCII mode, this should be transmitted using two characters. This example should be transmitted '61', which is a string of length two. This function does not handle that conversion for transmission. """

    _checkString(inputstring, description='input LRC string')

    register = 0
    for character in inputstring:
        register += ord(character)

    lrc = ((register ^ 0xFF) + 1) & 0xFF

    lrcString = _numToOneByteString(lrc)
    return lrcString