Bug with Detecting Merged Cells And Headers on fictitious bank statement

When running the notebook https://github.com/aws-samples/amazon-textract-code-samples/blob/master/python/Textract-Table-Merged-Cells-And-Headers.ipynb you get following error

`Traceback (most recent call last):

File "/opt/conda/lib/python3.7/site-packages/IPython/core/interactiveshell.py", line 3553, in run_code
exec(code_obj, self.user_global_ns, self.user_ns)

File "", line 5, in
from textractprettyprinter.t_pretty_print import Pretty_Print_Table_Format, Textract_Pretty_Print, get_string, get_tables_string

File "/opt/conda/lib/python3.7/site-packages/textractprettyprinter/__init__.py", line 3, in
from .t_pretty_print import Pretty_Print_Table_Format as Pretty_Print_Table_Format

File "/opt/conda/lib/python3.7/site-packages/textractprettyprinter/t_pretty_print.py", line 1, in
import trp

File "/opt/conda/lib/python3.7/site-packages/trp/__init__.py", line 31
print ip
^
SyntaxError: Missing parentheses in call to 'print'. Did you mean print(ip)?`

This is fixed by adding
`!pip install textract-trp`

Once that is fixed you get following error

`AttributeError: 'Table' object has no attribute 'get_header_field_names'`

首先运行 Textract-Table-Merged-Cells-And-Headers.ipynb，并检查其中对 textractprettyprinter 和 trp 的导入。检查导致 Python 3.7 SyntaxError 和缺少 Table.get_header_field_names 方法的包兼容性；当 notebook 在不出现这两个错误的情况下完成合并单元格和表头检测时，即表示完成。

由索引模型根据 Issue 内容生成。