how to check for roles in discord.py code example

Example: discord.py check if user has role

@bot.command(pass_context=True)
    @commands.has_role("Admin")
    async def unmute(ctx, user: discord.Member):
        role = discord.utils.find(lambda r: r.name == 'Member', ctx.message.server.roles)
        if role in user.roles:
            await bot.say("{} is not muted".format(user))
        else:
            await bot.add_roles(user, role)