1、去除字符串首尾空格、回车、 table
strip()
” xyz “.strip() # returns “xyz”
” xyz “.lstrip() # returns “xyz ”
” xyz “.rstrip() # returns ” xyz”
” x y z “.replace(’ ‘, ”) # returns “xyz”
2、函数：string.join()
3、python特殊方法
object._repr_(self)
Called by the repr() built-in function to compute the “official” string representation of an object. If at all possible, this should look like a valid Python expression that could be used to recreate an object with the same value (given an appropriate environment). If this is not possible, a string of the form <…some useful description…> should be returned. The return value must be a string object. If a class defines repr() but not str(), then repr() is also used when an “informal” string representation of instances of that class is required.
This is typically used for debugging, so it is important that the representation is information-rich and unambiguous.
object._str_(self)
Called by str(object) and the built-in functions format() and print() to compute the “informal” or nicely printable string representation of an object. The return value must be a string object.
This method differs from object.repr() in that there is no expectation that str() return a valid Python expression: a more convenient or concise representation can be used.
The default implementation defined by the built-in type object calls object.repr().
**4、round(2.675, 2)
小数保留位数
