new feature: open exists api in operator for python binding

[yihong0618]

Feature Description

https://opendal.apache.org/docs/rust/opendal/struct.Operator.html#method.exists
seems it is not in python binding and some repo need to use it

Problem and Solution

add it

Additional Context

No response

Are you willing to contribute to the development of this feature?

• Yes, I am willing to contribute to the development of this feature.

[Yashika-code]

@Xuanwo @yihong0618 Yes, I am willing to contribute to the development of this feature. Can you please explain it more how can i do that ?

[Xuanwo]

@Xuanwo @yihong0618 Yes, I am willing to contribute to the development of this feature. Can you please explain it more how can i do that ?

Hi, we need to implement an exists(&self, path: &str) -> PyResult<bool> like the following:

opendal/bindings/python/src/operator.rs

Lines 182 to 184 in a9d0ec6

	pub fn delete(&self, path: &str) -> PyResult<()> {
	self.core.delete(path).map_err(format_pyerr)
	}