chore: Deduplicate code from Python standard lib (#878)

* chore: Deduplicate code from Python standard lib

As we are supporting Python >= 3.6, we can rely on this function being
present in Python's standard library.

Co-authored-by: Johannes Sasongko <sasongko@gmail.com>

plugins/equalizer/__init__.py

@@ -26,6 +26,7 @@
 
 
 import logging
+import math
 import os
 
 from gi.repository import Gst
@@ -40,15 +41,6 @@
 logger = logging.getLogger('equalizer')
 
 
-def isclose(float_a, float_b, rel_tol=1e-09, abs_tol=0.0):
-    """
-    copied from python 3.5, where this function was introduced to the math module
-    """
-    return abs(float_a - float_b) <= max(
-        rel_tol * max(abs(float_a), abs(float_b)), abs_tol
-    )
-
-
 # Values from <http://www.xmms.org/faq.php#General3>, adjusted to be less loud
 # in general ((mean + max) / 2 = 0).
 DEFAULT_PRESETS = [
@@ -200,7 +192,7 @@ def adjust_band(self, widget):
         widget_name = Gtk.Buildable.get_name(widget)
         band = widget_name[-1]
         settings_value = settings.get_option("plugin/equalizer/band" + band)
-        if not isclose(widget.get_value(), settings_value):
+        if not math.isclose(widget.get_value(), settings_value):
             settings.set_option("plugin/equalizer/band" + band, widget.get_value())
             self.combo_presets.set_active(0)