Getting error object not callable in my program

OS : Windows 7
Python 2.7

total=0
temp =0
i=0;
j=1;
counter=0
MIN_val = 100
MAX_val = 0
file = open("C:/Users/Shrikanth/Desktop/Report.csv")
csv_reader = csv.reader(file)
next(csv_reader)

for all in csv_reader:
FileName, Channel, OrgSize, TransSize = all
if Channel == "TimesNow_LB":
total_redn= (float(OrgSize)- float(TransSize))/float(OrgSize) * 100
counter = counter + 1
MIN_val(float(total_redn))
MAX_val(float(total_redn))
AVG_val(float(total_redn))

print counter
def MIN_val(num):
global MIN_val
if MIN_val > num:
MIN_val = num
print MIN_val
def MAX_val(num):
global MAX_val
if MAX_val < num:
MAX_val=num
print MAX_val

So i'm getting ''MIN_val(float(total_redn))
TypeError: 'int' object is not callable'' error.
Why does it happen and what is the solution?

未识别出任何仓库文件或测试。使用 Python 2.7 重现所提供的代码片段，然后检查 MIN_val 和 MAX_val 的赋值、函数定义以及调用；当示例在没有报告的 TypeError 的情况下运行，并产生预期的最小值和最大值时，即表示完成。