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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 set_chars(self, array):
 """Set the characters used to draw lines between rows and columns - the array should contain 4 fields: [horizontal, vertical, corner, header] - default is set to: ['-', '|', '+', '='] """


        if len(array) != 4:
            raise ArraySizeError("array should contain 4 characters")
        array = [ x[:1] for x in [ str(s) for s in array ] ]
        (self._char_horiz, self._char_vert,
            self._char_corner, self._char_header) = array
        return self