<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_query_error(self,i):
 """Just get a single error characterization based on the index :param i: list index :type i: int :returns: base-wise error :rtype: HPA group description """

    x = self._query_hpas[i]
    h = x['hpa']
    pos = x['pos']
    prob = 0
    be = BaseError('query')
    be.set_observable(h.get_target(),h.get_query())
    if i != 0 and pos == 0: # check for a total deletion before
      prev = x['prev-hpa']
      if len(prev.get_query()) == 0: # total deletion
        be.set_unobserved_before(len(prev.get_target()),0,prev.get_target()[0],0.5)
    if i != len(self._query_hpas)-1 and pos == len(h.get_query())-1: # check for a total deletion before
      if x['next-hpa']:
        foll = x['next-hpa']
        if len(foll.get_query()) == 0: # total deletion
          be.set_unobserved_after(len(foll.get_target()),0,foll.get_target()[0],0.5)
    return be