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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 statement(self,phrase):
 """ log a one time statement Parameters phrase : str statement to log """

        t = datetime.now()
        s = str(t) + ' ' + str(phrase) + '\n'
        if self.echo:
            print(s,end='')
        if self.filename:
            self.f.write(s)
            self.f.flush()