Installed selenium2library version
Robot Framework 3.0.3.dev20170213 (Python 2.7.12 on win32)
Firefox - 52.0.2 (32-bit)
Selenium GeckoDriver v0.15 (https://github.com/mozilla/geckodriver/releases)
robotframework-selenium2library==1.7.4

c:\rfs2lib>python test/run_tests.py python firefox
Running unit tests
..................E..E..............................................................................EEE....

ERROR: test_create_webdriver (unit.keywords.test_browsermanagement.BrowserManagementTests)

Traceback (most recent call last):
File "c:\rfs2lib\test\unit\keywords\test_browsermanagement.py", line 116, in test_create_webdriver
self.assertEquals(capt_data['webdriver'], bm._current_browser())
File "c:\rfs2lib\test..\src\Selenium2Library\keywords_browsermanagement.py", line 515, in _current_browser
if not self._cache.current:
File "C:\Python27\lib\site-packages\future-0.16.0-py2.7.egg\future\types\newobject.py", line 88, in nonzero
return type(self).bool(self)
AttributeError: type object 'FakeWebDriver' has no attribute 'bool'

======================================================================
ERROR: test_set_selenium_timeout_only_affects_open_browsers (unit.keywords.test_browsermanagement.BrowserManagementTests)

Traceback (most recent call last):
File "c:\rfs2lib\test\unit\keywords\test_browsermanagement.py", line 85, in test_set_selenium_timeout_only_affects_open_browsers
bm._cache.close()
File "c:\rfs2lib\test..\src\Selenium2Library\utils\browsercache.py", line 21, in close
if self.current:
File "C:\Python27\lib\site-packages\future-0.16.0-py2.7.egg\future\types\newobject.py", line 88, in nonzero
return type(self).bool(self)
AttributeError: type object 'mock' has no attribute 'bool'

======================================================================
ERROR: test_close (unit.utils.test_browsercache.BrowserCacheTests)

Traceback (most recent call last):
File "c:\rfs2lib\test\unit\utils\test_browsercache.py", line 60, in test_close
cache.close()
File "c:\rfs2lib\test..\src\Selenium2Library\utils\browsercache.py", line 21, in close
if self.current:
File "C:\Python27\lib\site-packages\future-0.16.0-py2.7.egg\future\types\newobject.py", line 88, in nonzero
return type(self).bool(self)
AttributeError: type object 'mock' has no attribute 'bool'

======================================================================
ERROR: test_close_only_called_once (unit.utils.test_browsercache.BrowserCacheTests)

Traceback (most recent call last):
File "c:\rfs2lib\test\unit\utils\test_browsercache.py", line 74, in test_close_only_called_once
cache.close()
File "c:\rfs2lib\test..\src\Selenium2Library\utils\browsercache.py", line 21, in close
if self.current:
File "C:\Python27\lib\site-packages\future-0.16.0-py2.7.egg\future\types\newobject.py", line 88, in nonzero
return type(self).bool(self)
AttributeError: type object 'mock' has no attribute 'bool'

======================================================================
ERROR: test_get_open_browsers (unit.utils.test_browsercache.BrowserCacheTests)

Traceback (most recent call last):
File "c:\rfs2lib\test\unit\utils\test_browsercache.py", line 48, in test_get_open_browsers
cache.close()
File "c:\rfs2lib\test..\src\Selenium2Library\utils\browsercache.py", line 21, in close
if self.current:
File "C:\Python27\lib\site-packages\future-0.16.0-py2.7.egg\future\types\newobject.py", line 88, in nonzero
return type(self).bool(self)
AttributeError: type object 'mock' has no attribute 'bool'

Ran 107 tests in 0.062s

FAILED (errors=5)

5 unit tests failed - not running acceptance tests!

c:\rfs2lib>