parameters: (self, start, end)
docstring: Removes a link from the graph in all necessary ways: forward and reverse, and for reverse
          complements too.
docstring_summary: Removes a link from the graph in all necessary ways: forward and reverse, and for reverse
          complements too.
docstring_tokens: Removes a link from the graph in all necessary ways : forward and reverse and for reverse complements too .
function: def remove_link(self, start, end):
          """
          Removes a link from the graph in all necessary ways: forward and reverse, and for reverse
          complements too.
          """
          if start in self.forward_links:
              try:
                  self.forward_links[start].remove(end)
              except ValueError:
                  pass
              if len(self.forward_links[start]) == 0:
                  del self.forward_links[start]
          if -end in self.forward_links:
              try:
                  self.forward_links[-end].remove(-start)
              except ValueError:
                  pass
              if len(self.forward_links[-end]) == 0:
                  del self.forward_links[-end]
          if end in self.reverse_links:
              try:
                  self.reverse_links[end].remove(start)
              except ValueError:
                  pass
              if len(self.reverse_links[end]) == 0:
                  del self.reverse_links[end]
          if -start in self.reverse_links:
              try:
                  self.reverse_links[-start].remove(-end)
              except ValueError:
                  pass
              if len(self.reverse_links[-start]) == 0:
                  del self.reverse_links[-start]
function_tokens: def remove_link ( self , start , end ) : if start in self . forward_links : try : self . forward_links [ start ] . remove ( end ) except ValueError : pass if len ( self . forward_links [ start ] ) == 0 : del self . forward_links [ start ] if - end in self . forward_links : try : self . forward_links [ - end ] . remove ( - start ) except ValueError : pass if len ( self . forward_links [ - end ] ) == 0 : del self . forward_links [ - end ] if end in self . reverse_links : try : self . reverse_links [ end ] . remove ( start ) except ValueError : pass if len ( self . reverse_links [ end ] ) == 0 : del self . reverse_links [ end ] if - start in self . reverse_links : try : self . reverse_links [ - start ] . remove ( - end ) except ValueError : pass if len ( self . reverse_links [ - start ] ) == 0 : del self . reverse_links [ - start ]