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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 access_array(self, id_, lineno, scope=None, default_type=None):
 """ Called whenever an accessed variable is expected to be an array. ZX BASIC requires arrays to be declared before usage, so they're checked. Also checks for class array. """

        if not self.check_is_declared(id_, lineno, 'array', scope):
            return None

        if not self.check_class(id_, CLASS.array, lineno, scope):
            return None

        return self.access_id(id_, lineno, scope=scope, default_type=default_type)