Add python sample code (#11208)

* add initial python sample

* add all of ios and android tests

* apply formatter

* add >=0.28 to avoid version error

* tweak versions of default OS

* convert some tests to unittest based ones

* use single quote mainly

* use {} format style for string

* use format syntax

* apply format and tweak assertions

* use is None

* use assert raise

* speficy a number of elements

* tweak exception

* move app path to helper

* tweak assertion conditions

* remove .close since with open() close file automatically

sample-code/python/test/test_ios_basic_interactions.py

@@ -0,0 +1,47 @@
+import pytest
+import os
+
+from appium import webdriver
+from helpers import take_screenhot_and_syslog, IOS_APP_PATH, EXECUTOR
+
+
+class TestIOSBasicInteractions():
+
+    @pytest.fixture(scope='function')
+    def driver(self, request, device_logger):
+        calling_request = request._pyfuncitem.name
+        driver = webdriver.Remote(
+            command_executor=EXECUTOR,
+            desired_capabilities={
+                'app': IOS_APP_PATH,
+                'platformName': 'iOS',
+                'automationName': 'XCUITest',
+                'platformVersion': os.getenv('IOS_PLATFORM_VERSION') or '11.1',
+                'deviceName': os.getenv('IOS_DEVICE_NAME') or 'iPhone 6s',
+            }
+        )
+
+        def fin():
+            take_screenhot_and_syslog(driver, device_logger, calling_request)
+            driver.quit()
+
+        request.addfinalizer(fin)
+
+        driver.implicitly_wait(10)
+        return driver
+
+    def test_should_send_keys_to_inputs(self, driver):
+        text_field_el = driver.find_element_by_id('TextField1')
+        assert text_field_el.get_attribute('value') is None
+        text_field_el.send_keys('Hello World!')
+        assert 'Hello World!' == text_field_el.get_attribute('value')
+
+    def test_should_click_a_button_that_opens_an_alert(self, driver):
+        button_element_id = 'show alert'
+        button_element = driver.find_element_by_accessibility_id(button_element_id)
+        button_element.click()
+
+        alert_title_element_id = 'Cool title'
+        alert_title_element = driver.find_element_by_accessibility_id(alert_title_element_id)
+        alert_title = alert_title_element.get_attribute('name')
+        assert 'Cool title' == alert_title