Python-docx - How to change table font size? - python-2.7

Question

table = document.add_table(rows=1, cols=1)
hdr_cells = table.rows[0].cells
hdr_cells[0].text = 'Qty'
I have to change font size of text 'Qty' in table with one row and one column, how can I make it?

Answer 1

You need to get the paragraph in the cell. From the documentation of python-docx:
3.5.2 _Cell objects:
class docx.table._Cell (tc, parent)
paragraphs
List of paragraphs in the cell. A table cell is required to
contain at least one block-level element and end with a paragraph. By
default, a new cell contains a single paragraph. Read-only
Reference: python-docx Documentation - Read the Docs
The code:
To change font size of text 'Qty'
paragraph =hdr_cells[0].paragraphs[0]
run = paragraph.runs
font = run[0].font
font.size= Pt(30) # font size = 30
To change font size of the whole table:
for row in table.rows:
for cell in row.cells:
paragraphs = cell.paragraphs
for paragraph in paragraphs:
for run in paragraph.runs:
font = run.font
font.size= Pt(30)
Reference of how to access paragraphs in a table: Extracting data from tables

Answer 2

Up there the solution really helped. I use it for a while. But I found a tiny problem:time. As your table grows bigger the time you cost to build the table getting longer. So I improve it. Cut two rounds. Here you are:
The code changes the whole table
for row in table.rows:
for cell in row.cells:
paragraphs = cell.paragraphs
paragraph = paragraphs[0]
run_obj = paragraph.runs
run = run_obj[0]
font = run.font
font.size = Pt(30)
When you cut two rounds you save the time

Answer 3

Building on user7609283 answer, here is a short version to set a cell to bold (the cell must contain text before applying format as it looks for the first paragraph):
row_cells = table.add_row().cells
row_cells[0].text = "Customer"
row_cells[0].paragraphs[0].runs[0].font.bold = True

Answer 4

This font change applies to all cells of a table and is streamlined. All cells must contain text before being formatted or an index out of range error is thrown:
for row in table.rows:
for cell in row.cells:
cp = cell.paragraphs[0].runs
cp[0].font.size = Pt(14)
This next font change applies to a single cell as wanted, in this case the top left cell:
tc = table.cell(0, 0).paragraphs[0].runs
tc[0].font.size = Pt(14)