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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 code_timer(reset=False):
    '''Sets a global variable for tracking the timer accross multiple
    files '''

    global CODE_TIMER
    if reset:
        CODE_TIMER = CodeTimer()
    else:
        if CODE_TIMER is None:
            return CodeTimer()
        else:
            return CODE_TIMER