def append_overlap(self: ReadPair, other: ReadPair, skip: int = 1) -> ReadPair:
self_head = Read(self.data.head)
other_head = Read(other.data.head)
new_head = self_head.append_overlap(other_head)
new_head = new_head.data
self_tail = Read(self.data.tail)
other_tail = Read(other.data.tail)
new_tail = self_tail.append_overlap(other_tail)
new_tail = new_tail.data
# WARNING: new_d may go negative -- In the event of a negative d, it means that rather than there being a gap
# in between the head and tail, there's an OVERLAP in between the head and tail. To get rid of the overlap, you
# need to remove either the last d chars from head or first d chars from tail.
new_d = self.d - skip
kdmer = Kdmer(new_head, new_tail, new_d)
return ReadPair(kdmer, source=('overlap', [self, other]))
