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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 is_pk_descriptor(descriptor, include_alt=False):
 """Return true if `descriptor` is a primary key."""

    if descriptor.pk is True or type(descriptor.pk) is int:
        return True
    if include_alt:
        return descriptor.alt_pk is True or type(descriptor.alt_pk) is int
    else:
        return False