为什么不能重新安装python3.4或python3?

sudo apt-get install python3.4
Reading package lists... Done
Building dependency tree
Reading state information... Done
python3.4 is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 27 not upgraded.
3 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] y
Setting up python3-minimal (3.4.2-2) ...
/var/lib/dpkg/info/python3-minimal.postinst: 5: /var/lib/dpkg/info/python3-minimal.postinst: py3compile: not found
dpkg: error processing package python3-minimal (--configure):
 subprocess installed post-installation script returned error exit status 127
dpkg: dependency problems prevent configuration of python3:
 python3 depends on python3-minimal (= 3.4.2-2); however:
  Package python3-minimal is not configured yet.

dpkg: error processing package python3 (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of dh-python:
 dh-python depends on python3:any (>= 3.3.2-2~); however:
  Package python3 is not configured yet.

dpkg: error processing package dh-python (--configure):
 dependency problems - leaving unconfigured
Errors were encountered while processing:
 python3-minimal
 python3
 dh-python
E: Sub-process /usr/bin/dpkg returned an error code (1)
sudo apt-get install python3.4
Reading package