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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 getComponentByPosition(self, idx, default=noValue, instantiate=True):
 """Return |ASN.1| type component value by position. Equivalent to Python sequence subscription operation (e.g. `[]`). Parameters idx : :class:`int` Component index (zero-based). Must either refer to an existing component or to N+1 component (if *componentType* is set). In the latter case a new component type gets instantiated and appended to the |ASN.1| sequence. Keyword Args default: :class:`object` If set and requested component is a schema object, return the `default` object instead of the requested component. instantiate: :class:`bool` If `True` (default), inner component will be automatically instantiated. If 'False' either existing component or the `noValue` object will be returned. Returns ------- : :py:class:`~pyasn1.type.base.PyAsn1Item` Instantiate |ASN.1| component type or return existing component value Examples -------- .. code-block:: python # can also be SetOf class MySequenceOf(SequenceOf):
 componentType = OctetString() s = MySequenceOf() # returns component #0 with `.isValue` property False s.getComponentByPosition(0) # returns None s.getComponentByPosition(0, default=None) s.clear() # returns noValue s.getComponentByPosition(0, instantiate=False) # sets component #0 to OctetString() ASN.1 schema # object and returns it s.getComponentByPosition(0, instantiate=True) # sets component #0 to ASN.1 value object s.setComponentByPosition(0, 'ABCD') # returns OctetString('ABCD') value object s.getComponentByPosition(0, instantiate=False) s.clear() # returns noValue s.getComponentByPosition(0, instantiate=False) """

        try:
            componentValue = self._componentValues[idx]

        except IndexError:
            if not instantiate:
                return default

            self.setComponentByPosition(idx)

            componentValue = self._componentValues[idx]

        if default is noValue or componentValue.isValue:
            return componentValue
        else:
            return default