The easiest way to do this is with the discord.ext.commands
extension. Here we use a converter to get the target user, and a keyword-only argument as an optional message to send them:
from discord.ext import commands
import discord
bot = commands.Bot(command_prefix='!')
@bot.command(pass_context=True)
async def DM(ctx, user: discord.User, *, message=None):
message = message or "This Message is sent via DM"
await bot.send_message(user, message)
bot.run("TOKEN")
For the newer 1.0+ versions of discord.py, you should use send
instead of send_message
from discord.ext import commands
import discord
bot = commands.Bot(command_prefix='!')
@bot.command()
async def DM(ctx, user: discord.User, *, message=None):
message = message or "This Message is sent via DM"
await user.send(message)
bot.run("TOKEN")