InvalidSpecifier error using pipenv to install pytz specific version

[babaMar]

Issue description

pipenv raises InvalidSpecifier when trying to install pytz==2012h in requirements file

Expected result

package to be installed

Actual result

Traceback (most recent call last):
  File "/home/stefano/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 101, in <module>
    main()
  File "/home/stefano/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 90, in main
    system=system,
  File "/home/stefano/.local/lib/python3.6/site-packages/pipenv/resolver.py", line 73, in resolve
    allow_global=system,
  File "/home/stefano/.local/lib/python3.6/site-packages/pipenv/utils.py", line 453, in resolve_deps
    version = str(req.get_version())
  File "/home/stefano/.local/lib/python3.6/site-packages/pipenv/vendor/requirementslib/models/requirements.py", line 1008, in
get_version
    return parse_version(self.get_specifier().version)
  File "/home/stefano/.local/lib/python3.6/site-packages/pipenv/vendor/requirementslib/models/requirements.py", line 1005, in
get_specifier
    return Specifier(self.specifiers)
  File "/home/stefano/.local/lib/python3.6/site-packages/pipenv/vendor/packaging/specifiers.py", line 85, in __init__
    raise InvalidSpecifier("Invalid specifier: '{0}'".format(spec))
packaging.specifiers.InvalidSpecifier: Invalid specifier: '==2012h'
/home/stefano/.local/lib/python3.6/site-packages/pipenv/_compat.py:113: ResourceWarning: Implicitly cleaning up <TemporaryDirectory '/tmp/pipenv-q9klYm-requirements'>
  warnings.warn(warn_message, ResourceWarning)

Steps to replicate

Installed virtualenv with pipenv shell --python 2.7 and dependencies with pipenv install -r requirements.txt

---

$ pipenv --support

Pipenv version: '2018.10.13'

Pipenv location: '/home/stefano/.local/lib/python3.6/site-packages/pipenv'

Python location: '/usr/bin/python3'

Python installations found:

• 3.7.1: /usr/local/bin/python3.7m
• 3.7.1: /usr/local/bin/python3.7
• 3.6.6: /usr/bin/python3.6m
• 3.6.6: /usr/bin/python3.6
• 2.7.15rc1: /home/stefano/.local/share/virtualenvs/mailexpress-sender-Fmumk5VO/bin/python2.7
• 2.7.15rc1: /usr/bin/python2.7

PEP 508 Information:

{'implementation_name': 'cpython',
 'implementation_version': '3.6.6',
 'os_name': 'posix',
 'platform_machine': 'x86_64',
 'platform_python_implementation': 'CPython',
 'platform_release': '4.15.0-38-generic',
 'platform_system': 'Linux',
 'platform_version': '#41-Ubuntu SMP Wed Oct 10 10:59:38 UTC 2018',
 'python_full_version': '3.6.6',
 'python_version': '3.6',
 'sys_platform': 'linux'}

System environment variables:

• BYOBU_ACCENT
• BYOBU_BACKEND
• BYOBU_CHARMAP
• BYOBU_CONFIG_DIR
• BYOBU_DARK
• BYOBU_DATE
• BYOBU_DISTRO
• BYOBU_HIGHLIGHT
• BYOBU_LIGHT
• BYOBU_PAGER
• BYOBU_PREFIX
• BYOBU_PYTHON
• BYOBU_READLINK
• BYOBU_RUN_DIR
• BYOBU_SED
• BYOBU_TERM
• BYOBU_TIME
• BYOBU_TTY
• BYOBU_ULIMIT
• BYOBU_WINDOW_NAME
• COLORTERM
• COMPIZ_CONFIG_PROFILE
• DBUS_SESSION_BUS_ADDRESS
• DEFAULTS_PATH
• DESKTOP_SESSION
• DISPLAY
• GDMSESSION
• GDM_LANG
• GITHUB_DEPLOY_TOKEN
• GPG_AGENT_INFO
• GTK_MODULES
• GTK_OVERLAY_SCROLLING
• HOME
• LANG
• LANGUAGE
• LC_ADDRESS
• LC_CTYPE
• LC_IDENTIFICATION
• LC_MEASUREMENT
• LC_MONETARY
• LC_NAME
• LC_NUMERIC
• LC_PAPER
• LC_TELEPHONE
• LC_TIME
• LESS
• LOGNAME
• LSCOLORS
• LS_COLORS
• MANDATORY_PATH
• MATE_DESKTOP_SESSION_ID
• MEX_LAB
• OLDPWD
• PAGER
• PATH
• PWD
• QT_ACCESSIBILITY
• QT_AUTO_SCREEN_SCALE_FACTOR
• QT_QPA_PLATFORMTHEME
• QT_SCALE_FACTOR
• SESSION_MANAGER
• SHELL
• SHLVL
• SSH_AGENT_PID
• SSH_AUTH_SOCK
• TERM
• TMUX
• TMUX_PANE
• UBUNTU_MENUPROXY
• USER
• VTE_VERSION
• WINDOWID
• XAUTHORITY
• XDG_CONFIG_DIRS
• XDG_CURRENT_DESKTOP
• XDG_DATA_DIRS
• XDG_GREETER_DATA_DIR
• XDG_RUNTIME_DIR
• XDG_SEAT
• XDG_SEAT_PATH
• XDG_SESSION_DESKTOP
• XDG_SESSION_ID
• XDG_SESSION_PATH
• XDG_SESSION_TYPE
• XDG_VTNR
• ZSH
• _
• PYTHONDONTWRITEBYTECODE
• PIP_SHIMS_BASE_MODULE
• PIP_PYTHON_PATH
• PIPENV_ACTIVE
• VIRTUAL_ENV
• PS1

Pipenv–specific environment variables:

• PIPENV_ACTIVE: 1

Debug–specific environment variables:

• PATH: /home/stefano/.local/share/virtualenvs/mailexpress-sender-Fmumk5VO/bin:/home/stefano/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
• SHELL: /usr/bin/zsh
• LANG: en_US.UTF-8
• PWD: /home/stefano/CGProjects/customergauge-mex-lab/repos/mailexpress-sender
• VIRTUAL_ENV: /home/stefano/.local/share/virtualenvs/mailexpress-sender-Fmumk5VO

---

Contents of Pipfile ('/home/stefano/CGProjects/customergauge-mex-lab/repos/mailexpress-sender/Pipfile'):

[[source]]
url = "https://pypi.org/simple"
verify_ssl = true
name = "pypi"

[packages]
alembic = "==0.9.3"
"autopep8" = "==1.3.2"
"boto3" = "==1.5.31"
botocore = "==1.8.50"
certifi = "==2017.4.17"
chardet = "==3.0.4"
click = "==6.7"
configparser = "==3.5.0"
decorator = "==4.0.11"
docutils = "==0.14"
"enum34" = "==1.1.6"
first = "==2.0.1"
"flake8" = "==3.4.1"
funcsigs = "==1.0.2"
futures = "==3.2.0"
idna = "==2.5"
ipython = "==5.4.1"
jmespath = "==0.9.3"
mccabe = "==0.6.1"
mock = "==2.0.0"
nexmo = "==1.2.0"
"pathlib2" = "==2.3.0"
pbr = "==3.1.1"
pexpect = "==4.2.1"
pickleshare = "==0.7.4"
pip-tools = "==1.9.0"
psutil = "==5.2.2"
ptyprocess = "==0.5.2"
py = "==1.4.34"
pycodestyle = "==2.3.1"
pyflakes = "==1.5.0"
pytest = "==3.1.2"
pytest-mock = "==1.6.0"
python-dateutil = "==2.6.1"
python-editor = "==1.0.3"
python-json-logger = "==0.1.8"
pytz = "==2012h"
redis = "==2.7.6"
requests = "==2.18.1"
rq = "==0.10.0"
"s3transfer" = "==0.1.13"
scandir = "==1.5"
sendgrid = "==1.5.3"
simplegeneric = "==0.8.1"
six = "==1.10.0"
smtpapi = "==0.2.0"
traitlets = "==4.3.2"
"urllib3" = "==1.21.1"
wcwidth = "==0.1.7"
"backports.shutil_get_terminal_size" = "==1.0.0"
ipython_genutils = "==0.2.0"
Mako = "==1.0.7"
MarkupSafe = "==1.0"
prompt_toolkit = "==1.0.14"
Pygments = "==2.2.0"
PyMySQL = "==0.7.11"
SQLAlchemy = "==1.1.9"

[dev-packages]

[requires]
python_version = "2.7"