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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 getDateTimeFromGet(request,key):
    '''
    This function just parses the request GET data for the requested key,
    and returns it in datetime format, returning none if the key is not
    available or is in incorrect format.
    '''
    if request.GET.get(key,''):
        try:
            return ensure_timezone(datetime.strptime(unquote(request.GET.get(key,'')),'%Y-%m-%d'))
        except (ValueError, TypeError):
            pass
    return None