# Buggy code
def get_hash(self, path_info, **kwargs):
    assert path_info and (isinstance(path_info, str) or path_info.scheme == self.scheme)

    if not self.exists(path_info):
        return self.PARAM_CHECKSUM, None

    # pylint: disable=assignment-from-none
    hash_ = self.state.get(path_info)

    # If we have dir hash in state db, but dir cache file is lost,
    # then we need to recollect the dir via .get_dir_hash() call below,
    # see https://github.com/iterative/dvc/issues/2219 for context
    if (
        hash_
        and self.is_dir_hash(hash_)
        and not self.cache.tree.exists(self.cache.tree.hash_to_path_info(hash_))
    ):
        hash_ = None

    if hash_:
        return self.PARAM_CHECKSUM, hash_

    if self.isdir(path_info):
        typ, hash_ = self.get_dir_hash(path_info, **kwargs)
    else:
        typ, hash_ = self.get_file_hash(path_info)

    if hash_ and self.exists(path_info):
        self.state.save(path_info, hash_)

    return typ, hash_


# Traceback (dvc.exceptions.RemoteCacheRequiredError)
2020-07-01 17:14:02,947 DEBUG: fetched: [(3,)]
2020-07-01 17:14:03,123 DEBUG: Removing output 'some_target' of stage: 'some_target.dvc'.
Importing 's3://some_bucket/some_target' -> 'some_target'
2020-07-01 17:14:03,123 DEBUG: Computed stage: 'some_target.dvc' md5: '2f8b87d3b22efd1638f414c3b3f65614'
2020-07-01 17:14:03,123 DEBUG: 'md5' of stage: 'some_target.dvc' changed.
2020-07-01 17:14:04,088 DEBUG: fetched: [(0,)]
2020-07-01 17:14:04,146 ERROR: failed to import s3://some_bucket/some_target. You could also try downloading it manually, and adding it with `dvc add`. - Current operation was unsuccessful because 's3://some_bucket/some_target' requires existing cache on 's3' remote. See <https://man.dvc.org/config#cache> for information on how to set up remote cache.
------------------------------------------------------------
Traceback (most recent call last):
File "/usr/lib/python3.8/site-packages/dvc/command/imp_url.py", line 14, in run
self.repo.imp_url(
File "/usr/lib/python3.8/site-packages/dvc/repo/__init__.py", line 36, in wrapper
ret = f(repo, *args, **kwargs)
File "/usr/lib/python3.8/site-packages/dvc/repo/scm_context.py", line 4, in run
result = method(repo, *args, **kw)
File "/usr/lib/python3.8/site-packages/dvc/repo/imp_url.py", line 54, in imp_url
stage.run()
File "/home/anotherbugmaster/.local/lib/python3.8/site-packages/funcy/decorators.py", line 39, in wrapper
return deco(call, *dargs, **dkwargs)
File "/usr/lib/python3.8/site-packages/dvc/stage/decorators.py", line 35, in rwlocked
return call()
File "/home/anotherbugmaster/.local/lib/python3.8/site-packages/funcy/decorators.py", line 60, in __call__
return self._func(*self._args, **self._kwargs)
File "/usr/lib/python3.8/site-packages/dvc/stage/__init__.py", line 424, in run
sync_import(self, dry, force)
File "/usr/lib/python3.8/site-packages/dvc/stage/imports.py", line 29, in sync_import
stage.save_deps()
File "/usr/lib/python3.8/site-packages/dvc/stage/__init__.py", line 387, in save_deps
dep.save()
File "/usr/lib/python3.8/site-packages/dvc/output/base.py", line 268, in save
self.info = self.save_info()
File "/usr/lib/python3.8/site-packages/dvc/output/base.py", line 192, in save_info
return self.remote.save_info(self.path_info)
File "/usr/lib/python3.8/site-packages/dvc/remote/base.py", line 762, in save_info
return self.tree.save_info(path_info, **kwargs)
File "/usr/lib/python3.8/site-packages/dvc/remote/base.py", line 329, in save_info
self.PARAM_CHECKSUM: self.get_hash(path_info, tree=tree, **kwargs)
File "/usr/lib/python3.8/site-packages/dvc/remote/base.py", line 297, in get_hash
hash_ = self.get_dir_hash(path_info, tree, **kwargs)
File "/usr/lib/python3.8/site-packages/dvc/remote/base.py", line 311, in get_dir_hash
raise RemoteCacheRequiredError(path_info)
dvc.exceptions.RemoteCacheRequiredError: Current operation was unsuccessful because 's3://some_bucket/some_target' requires existing cache on 's3' remote. See <https://man.dvc.org/config#cache> for information on how to set up remote cache.
------------------------------------------------------------

Having any troubles? Hit us up at https://dvc.org/support, we are always happy to help!

# Fixed code
def get_hash(self, path_info, **kwargs):
    assert path_info and (isinstance(path_info, str) or path_info.scheme == self.scheme)

    if not self.exists(path_info):
        return None

    # pylint: disable=assignment-from-none
    hash_ = self.state.get(path_info)

    # If we have dir hash in state db, but dir cache file is lost,
    # then we need to recollect the dir via .get_dir_hash() call below,
    # see https://github.com/iterative/dvc/issues/2219 for context
    if (
        hash_
        and self.is_dir_hash(hash_)
        and not self.cache.tree.exists(self.cache.tree.hash_to_path_info(hash_))
    ):
        hash_ = None

    if hash_:
        return HashInfo(self.PARAM_CHECKSUM, hash_)

    if self.isdir(path_info):
        hash_info = self.get_dir_hash(path_info, **kwargs)
    else:
        hash_info = self.get_file_hash(path_info)

    if hash_info and self.exists(path_info):
        self.state.save(path_info, hash_info.value)

    return hash_info