'Rounds to an integer.
When the operand has a negative exponent, the result is the same
as using the quantize() operation using the given operand as the
left-hand-operand, 1E+0 as the right-hand-operand, and the precision
of the operand as the precision setting, except that no flags will
be set. The rounding mode is taken from the context.
>>> ExtendedContext.to_integral(Decimal(\'2.1\'))
Decimal("2")
>>> ExtendedContext.to_integral(Decimal(\'100\'))
Decimal("100")
>>> ExtendedContext.to_integral(Decimal(\'100.0\'))
Decimal("100")
>>> ExtendedContext.to_integral(Decimal(\'101.5\'))
Decimal("102")
>>> ExtendedContext.to_integral(Decimal(\'-101.5\'))
Decimal("-102")
>>> ExtendedContext.to_integral(Decimal(\'10E+5\'))
Decimal("1.0E+6")
>>> ExtendedContext.to_integral(Decimal(\'7.89E+77\'))
Decimal("7.89E+77")
>>> ExtendedContext.to_integral(Decimal(\'-Inf\'))
Decimal("-Infinity")'

def to_integral(self, a):

    return a.to_integral(context=self)
