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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 datetime_string(day, month, year, hour, minute):
 """Build a date string using the provided day, month, year numbers. Automatically adds a leading zero to ``day`` and ``month`` if they only have one digit. Args: day (int):
 Day number. month(int):
 Month number. year(int):
 Year number. hour (int):
 Hour of the day in 24h format. minute (int):
 Minute of the hour. Returns: str: Date in the format *YYYY-MM-DDThh:mm:ss*. """

    # Overflow
    if hour < 0 or hour > 23: hour = 0
    if minute < 0 or minute > 60: minute = 0

    return '%d-%02d-%02dT%02d:%02d:00' % (year, month, day, hour, minute)