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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 is_identity():
 """Check to see if this matrix is an identity matrix."""

        for index, row in enumerate(self.dta):
            if row[index] == 1:
                for num, element in enumerate(row):
                    if num != index:
                        if element != 0:
                            return False
            else:
                return False

        return True