error while installing pythia

Collecting pythia
  Using cached pythia-0.8.1.11.tar.gz (146 kB)
    ERROR: Command errored out with exit status 1:
     command: /usr/bin/python3 -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-2jqo7ch9/pythia/setup.py'"'"'; __file__='"'"'/tmp/pip-install-2jqo7ch9/pythia/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base /tmp/pip-install-2jqo7ch9/pythia/pip-egg-info
         cwd: /tmp/pip-install-2jqo7ch9/pythia/
    Complete output (15 lines):
    Traceback (most recent call last):
      File "/tmp/pip-install-2jqo7ch9/pythia/setup.py", line 3, in <module>
        from merlin import setup, find_packages
    ModuleNotFoundError: No module named 'merlin'

    During handling of the above exception, another exception occurred:

    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-install-2jqo7ch9/pythia/setup.py", line 6, in <module>
        from ez_setup import use_setuptools
      File "/tmp/pip-install-2jqo7ch9/pythia/ez_setup/__init__.py", line 110
        except pkg_resources.VersionConflict, e:
                                            ^
    SyntaxError: invalid syntax
    ----------------------------------------
ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.