title: Change matplotlib.slider label text size
body: <p>I want to make plots and change their properties with slider. But the label text of <code>matplotlib.widgets.Slider</code> is very small for my eyes. I surfed the internet to find the answer how to change it, but I had no luck. </p>
  
  <p>The crucial part of code is:</p>
  
  <pre><code>E0_slider_ax = fig.add_axes([0.6, 0.2, 0.25, 0.03], axisbg=axis_color)
  E0_slider = mw.Slider(E0_slider_ax, r'$\epsilon_0$', 1,  100, valinit = E0)
  # I want to make r'$\epsilon_0$' bigger
  </code></pre>
  
  <p>I tried to make text for the label as folows:</p>
  
  <pre><code>t = matplotlib.text.Text(r'$\epsilon_0$', size = 22)
  E0_slider = mw.Slider(E0_slider_ax, label = t, valmin = 1, valmax = 100, valinit = E0)
  </code></pre>
  
  <p>but it returns me an error:</p>
  
  <pre><code>Traceback (most recent call last):
  
    File "&lt;ipython-input-53-2310b0749547&gt;", line 1, in &lt;module&gt;
      runfile('C:/Users/Robert/Desktop/multidif_S.py', 
  wdir='C:/Users/Robert/Desktop')
  
    File "C:\Users\Robert\Desktop\WinPython-64bit-3.5.2.2\python-
  3.5.2.amd64\lib\site-
  packages\spyderlib\widgets\externalshell\sitecustomize.py", line 845, in 
  runfile
      execfile(filename, namespace)
  
    File "C:\Users\Robert\Desktop\WinPython-64bit-3.5.2.2\python-
  3.5.2.amd64\lib\site-
  packages\spyderlib\widgets\externalshell\sitecustomize.py", line 103, in 
  execfile
      exec(compile(f.read(), filename, 'exec'), namespace)
  
    File "C:/Users/Robert/Desktop/multidif_S.py", line 64, in &lt;module&gt;
      E0_slider = mw.Slider(E0_slider_ax, label = t, valmin = 1, valmax = 100, 
  valinit = E0)
  
    File "C:\Users\Robert\Desktop\WinPython-64bit-3.5.2.2\python-
  3.5.2.amd64\lib\site-packages\matplotlib\widgets.py", line 376, in __init__
      horizontalalignment='right')
  
    File "C:\Users\Robert\Desktop\WinPython-64bit-3.5.2.2\python-
  3.5.2.amd64\lib\site-packages\matplotlib\axes\_axes.py", line 623, in text
      x=x, y=y, text=s)
  
    File "C:\Users\Robert\Desktop\WinPython-64bit-3.5.2.2\python-
  3.5.2.amd64\lib\site-packages\matplotlib\text.py", line 220, in __init__
      self.set_text(text)
  
    File "C:\Users\Robert\Desktop\WinPython-64bit-3.5.2.2\python-
  3.5.2.amd64\lib\site-packages\matplotlib\text.py", line 1206, in set_text
      self._text = '%s' % (s,)
  
    File "C:\Users\Robert\Desktop\WinPython-64bit-3.5.2.2\python-
  3.5.2.amd64\lib\site-packages\matplotlib\text.py", line 186, in __str__
      return "Text(%g,%g,%s)" % (self._x, self._y, repr(self._text))
  
  TypeError: a float is required
  </code></pre>
  
  <p>thx for help!</p>