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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 decorator(func):
 """A function timer decorator."""


        def function_timer(*args, **kwargs):
            """A nested function for timing other functions."""
            # Capture start time
            start = time.time()

            # Execute function with arguments
            value = func(*args, **kwargs)

            # Capture end time
            end = time.time()

            # Calculate run time
            runtime = end - start
            if runtime < 60:
                runtime = str('sec: ' + str('{:f}'.format(runtime)))
            else:
                runtime = str('min: ' + str('{:f}'.format(runtime / 60)))
            print('{func:50} --> {time}'.format(func=func.__qualname__, time=runtime))
            return value

        return function_timer