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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 _mantissa(dval):
 """Extract the _mantissa bits from a double-precision floating point value."""


    bb = _double_as_bytes(dval)
    mantissa =  bb[1] & 0x0f << 48
    mantissa += bb[2] << 40
    mantissa += bb[3] << 32
    mantissa += bb[4]
    return mantissa