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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 datatype(dbtype, description, cursor):
 """Google AppEngine Helper to convert a data type into a string."""

    dt = cursor.db.introspection.get_field_type(dbtype, description)
    if type(dt) is tuple:
        return dt[0]
    else:
        return dt