How to change font size of chart title and axis title ?

[thrupass]

Hi, experts

I want to change font size of chart title and axis(x,y) title.
Can you help me ?

Thanks in advance

######################### BOF #######################################
### Python 3.6.3/ openpyxl 2.4.9
from datetime import date
from openpyxl import Workbook
from openpyxl.chart import (
LineChart,
Reference,
)
from openpyxl.chart.axis import DateAxis

wb = Workbook()
ws = wb.active

rows = [
['Date', 'Batch 1', 'Batch 2', 'Batch 3'],
[date(2015,9, 1), 40, 30, 25],
[date(2015,9, 2), 40, 25, 30],
[date(2015,9, 3), 50, 30, 45],
[date(2015,9, 4), 30, 25, 40],
[date(2015,9, 5), 25, 35, 30],
[date(2015,9, 6), 20, 40, 35],
]

for row in rows:
ws.append(row)

c1 = LineChart()
c1.title = "Line Chart"
c1.style = 13
c1.y_axis.title = 'Size'
c1.x_axis.title = 'Test Number'

data = Reference(ws, min_col=2, min_row=1, max_col=4, max_row=7)
c1.add_data(data, titles_from_data=True)

# Style the lines
s1 = c1.series[0]
s1.marker.symbol = "triangle"
s1.marker.graphicalProperties.solidFill = "FF0000" # Marker filling
s1.marker.graphicalProperties.line.solidFill = "FF0000" # Marker outline

s1.graphicalProperties.line.noFill = True

s2 = c1.series[1]
s2.graphicalProperties.line.solidFill = "00AAAA"
s2.graphicalProperties.line.dashStyle = "sysDot"
s2.graphicalProperties.line.width = 100050 # width in EMUs

s2 = c1.series[2]
s2.smooth = True # Make the line smooth
ws.add_chart(c1, "A10")
wb.save("line.xlsx")