Aug 18, 2020 · Aug 16, 2020
diff --git a/doc/api/next_api_changes/behavior/18203-DS.rst b/doc/api/next_api_changes/behavior/18203-DS.rst
 Locators and formatters
 ~~~~~~~~~~~~~~~~~~~~~~~

 Axis locators and formatters must now be subclasses of
 `~matplotlib.ticker.Locator` and `~matplotlib.ticker.Formatter` respectively.
diff --git a/lib/matplotlib/axis.py b/lib/matplotlib/axis.py
    @locator.setter
    def locator(self, locator):
        if not isinstance(locator, mticker.Locator):
            cbook.warn_deprecated(
                "3.2", message="Support for locators that do not subclass "
                "matplotlib.ticker.Locator is deprecated since %(since)s and "
                "support for them will be removed %(removal)s.")
            raise TypeError('locator must be a subclass of '
                            'matplotlib.ticker.Locator')
        self._locator = locator

    @property
    @formatter.setter
    def formatter(self, formatter):
        if not isinstance(formatter, mticker.Formatter):
            cbook.warn_deprecated(
                "3.2", message="Support for formatters that do not subclass "
                "matplotlib.ticker.Formatter is deprecated since %(since)s "
                "and support for them will be removed %(removal)s.")
            raise TypeError('formatter must be a subclass of '
                            'matplotlib.ticker.Formatter')
        self._formatter = formatter
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,5 @@
		Locators and formatters
		~~~~~~~~~~~~~~~~~~~~~~~

		Axis locators and formatters must now be subclasses of
		`~matplotlib.ticker.Locator` and `~matplotlib.ticker.Formatter` respectively.
Original file line number	Diff line number	Diff line change
Expand Up		@@ -577,10 +577,8 @@ def locator(self):
		@locator.setter
		def locator(self, locator):
		if not isinstance(locator, mticker.Locator):
		cbook.warn_deprecated(
		"3.2", message="Support for locators that do not subclass "
		"matplotlib.ticker.Locator is deprecated since %(since)s and "
		"support for them will be removed %(removal)s.")
		raise TypeError('locator must be a subclass of '
		'matplotlib.ticker.Locator')
		self._locator = locator

		@property
Expand All		@@ -590,10 +588,8 @@ def formatter(self):
		@formatter.setter
		def formatter(self, formatter):
		if not isinstance(formatter, mticker.Formatter):
		cbook.warn_deprecated(
		"3.2", message="Support for formatters that do not subclass "
		"matplotlib.ticker.Formatter is deprecated since %(since)s "
		"and support for them will be removed %(removal)s.")
		raise TypeError('formatter must be a subclass of '
		'matplotlib.ticker.Formatter')
		self._formatter = formatter


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