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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 append(self, other):
 """Appends another array to this array. The returned array will have all of the class methods and virutal fields of this array, including any that were added using `add_method` or `add_virtualfield`. If this array and other array have one or more string fields, the dtype for those fields are updated to a string length that can encompass the longest string in both arrays. .. note:: Increasing the length of strings only works for fields, not sub-fields. Parameters other : array The array to append values from. It must have the same fields and dtype as this array, modulo the length of strings. If the other array does not have the same dtype, a TypeError is raised. Returns ------- array An array with others values appended to this array's values. The returned array is an instance of the same class as this array, including all methods and virtual fields. """

        try:
            return numpy.append(self, other).view(type=self.__class__)
        except TypeError:
            # see if the dtype error was due to string fields having different
            # lengths; if so, we'll make the joint field the larger of the
            # two
            str_fields = [name for name in self.fieldnames
                          if _isstring(self.dtype[name])]
            # get the larger of the two
            new_strlens = dict(
                [[name,
                  max(self.dtype[name].itemsize, other.dtype[name].itemsize)]
                 for name in str_fields]
            )
            # cast both to the new string lengths
            new_dt = []
            for dt in self.dtype.descr:
                name = dt[0]
                if name in new_strlens:
                    dt = (name, self.dtype[name].type, new_strlens[name])
                new_dt.append(dt)
            new_dt = numpy.dtype(new_dt)
            return numpy.append(
                self.astype(new_dt),
                other.astype(new_dt)
                ).view(type=self.__class__)