title: Can not concatenate string with int in purge command
body: <p>I want the bot to say the following:</p>
  <pre><code>&quot;channel successfully purged, cleared {amount} messages&quot;
  </code></pre>
  <p>where <code>amount</code> is the amount of messages that have been purged.</p>
  <p>But, I've been getting this error:</p>
  <pre><code>discord.ext.commands.errors.CommandInvokeError: Command raised an exception: TypeError: '&lt;=' not supported between instances of 'str' and 'int'
  </code></pre>
  <p>This is the code I have right now:</p>
  <pre class="lang-py prettyprint-override"><code>@client.command()
  @commands.check(is_owner)
  async def purge(ctx, amount):
      await ctx.channel.purge(limit = amount)
      asyncio.wait(2)
      await ctx.send(&quot;channel successfully purged, cleared {amount} messages&quot;)
  </code></pre>
  <p>I tried adding <code>await ctx.send(f&quot;channel successfully purged, cleared {amount} messages&quot;)</code>, but it gives me the same error.</p>