docs: add __all__ variables to some modules

src/icalendar/cal.py

@@ -764,3 +764,8 @@ def example(cls, name) -> Calendar:
 # These are read only singleton, so one instance is enough for the module
 types_factory = TypesFactory()
 component_factory = ComponentFactory()
+
+__all__ = ["Alarm", "Calendar", "Component", "ComponentFactory", "Event",
+           "FreeBusy", "INLINE", "Journal", "Timezone", "TimezoneDaylight",
+           "TimezoneStandard", "Todo", "component_factory", "dateutil",
+           "types_factory"]

src/icalendar/caselessdict.py

@@ -106,3 +106,6 @@ def sorted_items(self):
         Items not specified in canonical_order will appear at the end.
         """
         return canonsort_items(self, self.canonical_order)
+
+
+__all__ = ["canonsort_keys", "canonsort_items", "CaselessDict"]

src/icalendar/parser.py

@@ -384,3 +384,11 @@ def from_ical(cls, st):
 
 # XXX: what kind of hack is this? import depends to be at end
 from icalendar.prop import vText
+
+
+__all__ = ["Contentline", "Contentlines", "FOLD", "NAME", "NEWLINE",
+           "Parameters", "QUNSAFE_CHAR", "QUOTABLE", "UNSAFE_CHAR", "dquote",
+           "escape_char", "escape_string", "foldline", "param_value", "q_join",
+           "q_split", "tzid_from_dt", "uFOLD", "unescape_char",
+           "unescape_list_or_string", "unescape_string", "validate_param_value",
+           "validate_token"]

src/icalendar/parser_tools.py

@@ -48,3 +48,7 @@ def data_encode(data: Union[ICAL_TYPE, dict, list], encoding=DEFAULT_ENCODING) -
         return list(map(data_encode, data))
     else:
         return data
+
+
+__all__ = ["DEFAULT_ENCODING", "SEQUENCE_TYPES", "data_encode", "from_unicode",
+           "to_unicode"]

src/icalendar/prop.py

@@ -1122,3 +1122,4 @@ def from_ical(self, name, value):
         type_class = self.for_property(name)
         decoded = type_class.from_ical(value)
         return decoded
+

src/icalendar/timezone/provider.py

@@ -43,3 +43,5 @@ def uses_pytz(self) -> bool:
     @abstractmethod
     def uses_zoneinfo(self) -> bool:
         """Whether we use zoneinfo."""
+
+__all__ = ["TZProvider"]

src/icalendar/tools.py

@@ -31,3 +31,5 @@ def uid(host_name='example.com', unique=''):
         unique = unique or UIDGenerator.rnd_string()
         today = to_unicode(vDatetime(datetime.today()).to_ical())
         return vText(f'{today}-{unique}@{host_name}')
+
+__all__ = ["UIDGenerator"]