'Sets the modification and access time of a file or directory.
Setting *one single time paramater* to -1 means that time parameter
must not be set by this call.
Setting *both time parameters* to -1 means both of them must be set to
the current time.
Parameters:
- ctx
- path: Path of the file or directory.
- atime: Access time in milliseconds since 1970-01-01 00:00 UTC
- mtime: Modification time in milliseconds since 1970-01-01 00:00 UTC'

def utime(self, ctx, path, atime, mtime):

    self.send_utime(ctx, path, atime, mtime)
    self.recv_utime()
