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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, data, itemsize=None):
 """ Append data to the end. Parameters data : array_like An array, any object exposing the array interface, an object whose __array__ method returns an array, or any (nested) sequence. itemsize: int or 1-D array If `itemsize is an integer, N, the array will be divided into elements of size N. If such partition is not possible, an error is raised. If `itemsize` is 1-D array, the array will be divided into elements whose succesive sizes will be picked from itemsize. If the sum of itemsize values is different from array size, an error is raised. """


        self.insert(len(self), data, itemsize)