dict.keys() is nearly always useless.

Author: anntzer

doc/sphinxext/gen_gallery.py

@@ -152,7 +152,7 @@ def gen_gallery(app, doctree):
             fh.write(content)
 
     for key in app.builder.status_iterator(
-            iter(thumbnails.keys()), "generating thumbnails... ",
+            iter(thumbnails), "generating thumbnails... ",
             length=len(thumbnails)):
         if out_of_date(key, thumbnails[key]):
             image.thumbnail(key, thumbnails[key], 0.3)

doc/sphinxext/gen_rst.py

@@ -51,8 +51,7 @@ def generate_example_rst(app):
             relpath = os.path.split(root)[-1]
             datad.setdefault(relpath, []).append((fullpath, fname, contents))
 
-    subdirs = list(datad.keys())
-    subdirs.sort()
+    subdirs = sorted(datad)
 
     fhindex = open(os.path.join(exampledir, 'index.rst'), 'w')
     fhindex.write("""\

examples/pylab_examples/fancybox_demo2.py

@@ -8,11 +8,11 @@
 fig1 = plt.figure(1, (4/1.5, figheight/1.5))
 fontsize = 0.3 * 72
 
-for i, stylename in enumerate(sorted(styles.keys())):
-    fig1.text(0.5, (spacing * (float(len(styles)) - i) - 0.5)/figheight, stylename,
+for i, stylename in enumerate(sorted(styles)):
+    fig1.text(0.5, (spacing * (len(styles) - i) - 0.5) / figheight, stylename,
               ha="center",
               size=fontsize,
               transform=fig1.transFigure,
               bbox=dict(boxstyle=stylename, fc="w", ec="k"))
-plt.draw()
+
 plt.show()

examples/statistics/bxp_demo.py

@@ -32,7 +32,7 @@
     stats[n]['med'] = np.median(data)
     stats[n]['mean'] *= 2
 
-print(stats[0].keys())
+print(list(stats[0]))
 
 fs = 10  # fontsize
 

examples/units/basic_units.py

@@ -17,9 +17,9 @@ def __get__(self, obj, objtype=None):
         return self.proxy_type(self.fn_name, obj)
 
 
-class TaggedValueMeta (type):
+class TaggedValueMeta(type):
     def __init__(cls, name, bases, dict):
-        for fn_name in cls._proxies.keys():
+        for fn_name in cls._proxies:
             try:
                 dummy = getattr(cls, fn_name)
             except AttributeError:

examples/user_interfaces/toolmanager.py

@@ -24,18 +24,16 @@ class ListTools(ToolBase):
 
     def trigger(self, *args, **kwargs):
         print('_' * 80)
-        print("{0:12} {1:45} {2}".format('Name (id)',
-                                         'Tool description',
-                                         'Keymap'))
+        print("{0:12} {1:45} {2}".format(
+            'Name (id)', 'Tool description', 'Keymap'))
         print('-' * 80)
         tools = self.toolmanager.tools
-        for name in sorted(tools.keys()):
+        for name in sorted(tools):
             if not tools[name].description:
                 continue
             keys = ', '.join(sorted(self.toolmanager.get_tool_keymap(name)))
-            print("{0:12} {1:45} {2}".format(name,
-                                             tools[name].description,
-                                             keys))
+            print("{0:12} {1:45} {2}".format(
+                name, tools[name].description, keys))
         print('_' * 80)
         print("Active Toggle tools")
         print("{0:12} {1:45}".format("Group", "Active"))

lib/matplotlib/__init__.py

@@ -916,8 +916,9 @@ def __setitem__(self, key, val):
                 raise ValueError("Key %s: %s" % (key, str(ve)))
             dict.__setitem__(self, key, cval)
         except KeyError:
-            raise KeyError('%s is not a valid rc parameter.\
-See rcParams.keys() for a list of valid parameters.' % (key,))
+            raise KeyError(
+                '%s is not a valid rc parameter. See rcParams.keys() for a '
+                'list of valid parameters.' % (key,))
 
     def __getitem__(self, key):
         inverse_alt = None
@@ -974,7 +975,7 @@ def values(self):
         """
         Return values in order of sorted keys.
         """
-        return [self[k] for k in self.keys()]
+        return [self[k] for k in self]
 
     def find_all(self, pattern):
         """

lib/matplotlib/afm.py

@@ -199,10 +199,9 @@ def _parse_char_metrics(fh):
         if line.startswith('EndCharMetrics'):
             return ascii_d, name_d
         # Split the metric line into a dictonary, keyed by metric identifiers
-        vals = filter(lambda s: len(s) > 0, line.split(';'))
-        vals = dict(map(lambda s: tuple(s.strip().split(' ', 1)), vals))
+        vals = dict(s.strip().split(' ', 1) for s in line.split(';') if s)
         # There may be other metrics present, but only these are needed
-        if any([id not in vals.keys() for id in ('C', 'WX', 'N', 'B')]):
+        if not {'C', 'WX', 'N', 'B'}.issubset(vals):
             raise RuntimeError('Bad char metrics line: %s' % line)
         num = _to_int(vals['C'])
         wx = _to_float(vals['WX'])

lib/matplotlib/animation.py

@@ -108,7 +108,7 @@ def reset_available_writers(self):
     def list(self):
         ''' Get a list of available MovieWriters.'''
         self.ensure_not_dirty()
-        return list(self.avail.keys())
+        return list(self.avail)
 
     def is_available(self, name):
         '''Check if given writer is available by name.

lib/matplotlib/axes/_base.py

@@ -2942,7 +2942,7 @@ def set_xscale(self, value, **kwargs):
         """
         # If the scale is being set to log, clip nonposx to prevent headaches
         # around zero
-        if value.lower() == 'log' and 'nonposx' not in kwargs.keys():
+        if value.lower() == 'log' and 'nonposx' not in kwargs:
             kwargs['nonposx'] = 'clip'
 
         g = self.get_shared_x_axes()
@@ -3222,7 +3222,7 @@ def set_yscale(self, value, **kwargs):
         """
         # If the scale is being set to log, clip nonposy to prevent headaches
         # around zero
-        if value.lower() == 'log' and 'nonposy' not in kwargs.keys():
+        if value.lower() == 'log' and 'nonposy' not in kwargs:
             kwargs['nonposy'] = 'clip'
 
         g = self.get_shared_y_axes()