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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 make_sqlalchemy_column(col, colname, constraints=True):
 """ Infer an appropriate SQLAlchemy column type based on a sequence of values. Keyword arguments: col : sequence A sequence of values to use to infer type, length etc. colname : string Name of column constraints : bool If True use length and nullable constraints """


    import sqlalchemy

    col_not_none = [v for v in col if v is not None]
    sql_column_kwargs = {}
    sql_type_kwargs = {}

    if len(col_not_none) == 0:
        sql_column_type = sqlalchemy.String
        if constraints:
            sql_type_kwargs['length'] = NULL_COLUMN_MAX_LENGTH

    elif all(isinstance(v, bool) for v in col_not_none):
        sql_column_type = sqlalchemy.Boolean

    elif all(isinstance(v, int) for v in col_not_none):
        if max(col_not_none) > SQL_INTEGER_MAX \
                or min(col_not_none) < SQL_INTEGER_MIN:
            sql_column_type = sqlalchemy.BigInteger
        else:
            sql_column_type = sqlalchemy.Integer

    elif all(isinstance(v, long) for v in col_not_none):
        sql_column_type = sqlalchemy.BigInteger

    elif all(isinstance(v, (int, long)) for v in col_not_none):
        sql_column_type = sqlalchemy.BigInteger

    elif all(isinstance(v, (int, long, float)) for v in col_not_none):
        sql_column_type = sqlalchemy.Float

    elif all(isinstance(v, datetime.datetime) for v in col_not_none):
        sql_column_type = sqlalchemy.DateTime

    elif all(isinstance(v, datetime.date) for v in col_not_none):
        sql_column_type = sqlalchemy.Date

    elif all(isinstance(v, datetime.time) for v in col_not_none):
        sql_column_type = sqlalchemy.Time

    else:
        sql_column_type = sqlalchemy.String
        if constraints:
            sql_type_kwargs['length'] = max([len(text_type(v)) for v in col])

    if constraints:
        sql_column_kwargs['nullable'] = len(col_not_none) < len(col)

    return sqlalchemy.Column(colname, sql_column_type(**sql_type_kwargs),
                             **sql_column_kwargs)