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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 _setBitOn(x, bitNum):
 """Set bit 'bitNum' to True. Args: * x (int):
 The value before. * bitNum (int):
 The bit number that should be set to True. Returns: The value after setting the bit. This is an integer. For example: For x = 4 (dec) = 0100 (bin), setting bit number 0 results in 0101 (bin) = 5 (dec). """

    _checkInt(x, minvalue=0, description='input value')
    _checkInt(bitNum, minvalue=0, description='bitnumber')

    return x | (1 << bitNum)