style: format code with black
diff --git a/erpnext/www/book_appointment/index.py b/erpnext/www/book_appointment/index.py
index 8cda3c1..06e99da 100644
--- a/erpnext/www/book_appointment/index.py
+++ b/erpnext/www/book_appointment/index.py
@@ -11,38 +11,46 @@
 
 
 def get_context(context):
-	is_enabled = frappe.db.get_single_value('Appointment Booking Settings', 'enable_scheduling')
+	is_enabled = frappe.db.get_single_value("Appointment Booking Settings", "enable_scheduling")
 	if is_enabled:
 		return context
 	else:
-		frappe.redirect_to_message(_("Appointment Scheduling Disabled"), _("Appointment Scheduling has been disabled for this site"),
-			http_status_code=302, indicator_color="red")
+		frappe.redirect_to_message(
+			_("Appointment Scheduling Disabled"),
+			_("Appointment Scheduling has been disabled for this site"),
+			http_status_code=302,
+			indicator_color="red",
+		)
 		raise frappe.Redirect
 
+
 @frappe.whitelist(allow_guest=True)
 def get_appointment_settings():
-	settings = frappe.get_doc('Appointment Booking Settings')
-	settings.holiday_list = frappe.get_doc('Holiday List', settings.holiday_list)
+	settings = frappe.get_doc("Appointment Booking Settings")
+	settings.holiday_list = frappe.get_doc("Holiday List", settings.holiday_list)
 	return settings
 
+
 @frappe.whitelist(allow_guest=True)
 def get_timezones():
 	import pytz
+
 	return pytz.all_timezones
 
+
 @frappe.whitelist(allow_guest=True)
 def get_appointment_slots(date, timezone):
 	# Convert query to local timezones
-	format_string = '%Y-%m-%d %H:%M:%S'
-	query_start_time = datetime.datetime.strptime(date + ' 00:00:00', format_string)
-	query_end_time = datetime.datetime.strptime(date + ' 23:59:59', format_string)
+	format_string = "%Y-%m-%d %H:%M:%S"
+	query_start_time = datetime.datetime.strptime(date + " 00:00:00", format_string)
+	query_end_time = datetime.datetime.strptime(date + " 23:59:59", format_string)
 	query_start_time = convert_to_system_timezone(timezone, query_start_time)
 	query_end_time = convert_to_system_timezone(timezone, query_end_time)
 	now = convert_to_guest_timezone(timezone, datetime.datetime.now())
 
 	# Database queries
-	settings = frappe.get_doc('Appointment Booking Settings')
-	holiday_list = frappe.get_doc('Holiday List', settings.holiday_list)
+	settings = frappe.get_doc("Appointment Booking Settings")
+	holiday_list = frappe.get_doc("Holiday List", settings.holiday_list)
 	timeslots = get_available_slots_between(query_start_time, query_end_time, settings)
 
 	# Filter and convert timeslots
@@ -58,15 +66,15 @@
 			converted_timeslots.append(dict(time=converted_timeslot, availability=True))
 		else:
 			converted_timeslots.append(dict(time=converted_timeslot, availability=False))
-	date_required = datetime.datetime.strptime(date + ' 00:00:00', format_string).date()
+	date_required = datetime.datetime.strptime(date + " 00:00:00", format_string).date()
 	converted_timeslots = filter_timeslots(date_required, converted_timeslots)
 	return converted_timeslots
 
+
 def get_available_slots_between(query_start_time, query_end_time, settings):
 	records = _get_records(query_start_time, query_end_time, settings)
 	timeslots = []
-	appointment_duration = datetime.timedelta(
-		minutes=settings.appointment_duration)
+	appointment_duration = datetime.timedelta(minutes=settings.appointment_duration)
 	for record in records:
 		if record.day_of_week == WEEKDAYS[query_start_time.weekday()]:
 			current_time = _deltatime_to_datetime(query_start_time, record.from_time)
@@ -82,33 +90,35 @@
 
 @frappe.whitelist(allow_guest=True)
 def create_appointment(date, time, tz, contact):
-	format_string = '%Y-%m-%d %H:%M:%S'
+	format_string = "%Y-%m-%d %H:%M:%S"
 	scheduled_time = datetime.datetime.strptime(date + " " + time, format_string)
 	# Strip tzinfo from datetime objects since it's handled by the doctype
-	scheduled_time = scheduled_time.replace(tzinfo = None)
+	scheduled_time = scheduled_time.replace(tzinfo=None)
 	scheduled_time = convert_to_system_timezone(tz, scheduled_time)
-	scheduled_time = scheduled_time.replace(tzinfo = None)
+	scheduled_time = scheduled_time.replace(tzinfo=None)
 	# Create a appointment document from form
-	appointment = frappe.new_doc('Appointment')
+	appointment = frappe.new_doc("Appointment")
 	appointment.scheduled_time = scheduled_time
 	contact = json.loads(contact)
-	appointment.customer_name = contact.get('name', None)
-	appointment.customer_phone_number = contact.get('number', None)
-	appointment.customer_skype = contact.get('skype', None)
-	appointment.customer_details = contact.get('notes', None)
-	appointment.customer_email = contact.get('email', None)
-	appointment.status = 'Open'
+	appointment.customer_name = contact.get("name", None)
+	appointment.customer_phone_number = contact.get("number", None)
+	appointment.customer_skype = contact.get("skype", None)
+	appointment.customer_details = contact.get("notes", None)
+	appointment.customer_email = contact.get("email", None)
+	appointment.status = "Open"
 	appointment.insert()
 	return appointment
 
+
 # Helper Functions
 def filter_timeslots(date, timeslots):
 	filtered_timeslots = []
 	for timeslot in timeslots:
-		if(timeslot['time'].date() == date):
+		if timeslot["time"].date() == date:
 			filtered_timeslots.append(timeslot)
 	return filtered_timeslots
 
+
 def convert_to_guest_timezone(guest_tz, datetimeobject):
 	guest_tz = pytz.timezone(guest_tz)
 	local_timezone = pytz.timezone(frappe.utils.get_time_zone())
@@ -116,15 +126,18 @@
 	datetimeobject = datetimeobject.astimezone(guest_tz)
 	return datetimeobject
 
-def convert_to_system_timezone(guest_tz,datetimeobject):
+
+def convert_to_system_timezone(guest_tz, datetimeobject):
 	guest_tz = pytz.timezone(guest_tz)
 	datetimeobject = guest_tz.localize(datetimeobject)
 	system_tz = pytz.timezone(frappe.utils.get_time_zone())
 	datetimeobject = datetimeobject.astimezone(system_tz)
 	return datetimeobject
 
+
 def check_availabilty(timeslot, settings):
-	return frappe.db.count('Appointment', {'scheduled_time': timeslot}) < settings.number_of_agents
+	return frappe.db.count("Appointment", {"scheduled_time": timeslot}) < settings.number_of_agents
+
 
 def _is_holiday(date, holiday_list):
 	for holiday in holiday_list.holidays:
@@ -136,7 +149,10 @@
 def _get_records(start_time, end_time, settings):
 	records = []
 	for record in settings.availability_of_slots:
-		if record.day_of_week == WEEKDAYS[start_time.weekday()] or record.day_of_week == WEEKDAYS[end_time.weekday()]:
+		if (
+			record.day_of_week == WEEKDAYS[start_time.weekday()]
+			or record.day_of_week == WEEKDAYS[end_time.weekday()]
+		):
 			records.append(record)
 	return records
 
@@ -148,4 +164,4 @@
 
 def _datetime_to_deltatime(date_time):
 	midnight = datetime.datetime.combine(date_time.date(), datetime.time.min)
-	return (date_time-midnight)
+	return date_time - midnight