Installation fails on Ubuntu Docker image

[nicolinux]

Installation fails because of a missing dep (ldap). Would be nice to skip this - I don't need LDAP in this case.

Installing collected packages: hashids, Django, django-gravatar2, pyldap, django-auth-ldap, static3, dj-static, djangorestframework, psycopg2, djorm-ext-pgfulltext, pytz, idna, pyasn1, six, pycparser, cffi, cryptography, gunicorn, teamvault
Running setup.py install for hashids ... done
Running setup.py install for pyldap ... error
Complete output from command /usr/bin/python3 -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-y3r0w2bq/pyldap/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-tctl7av0-record/install-record.txt --single-version-externally-managed --compile:
defines: HAVE_SASL HAVE_TLS HAVE_LIBLDAP_R
extra_compile_args:
extra_objects:
include_dirs: /usr/include /usr/include/sasl /usr/local/include /usr/local/include/sasl
library_dirs: /usr/lib /usr/lib64 /usr/local/lib /usr/local/lib64
libs: ldap_r
running install
running build
running build_py
file Lib/ldap.py (for module ldap) not found
file Lib/ldap/controls.py (for module ldap.controls) not found
file Lib/ldap/extop.py (for module ldap.extop) not found
file Lib/ldap/schema.py (for module ldap.schema) not found
creating build
creating build/lib.linux-x86_64-3.5
copying Lib/ldapurl.py -> build/lib.linux-x86_64-3.5
copying Lib/ldif.py -> build/lib.linux-x86_64-3.5
copying Lib/dsml.py -> build/lib.linux-x86_64-3.5
creating build/lib.linux-x86_64-3.5/ldap
copying Lib/ldap/__init__.py -> build/lib.linux-x86_64-3.5/ldap
copying Lib/ldap/async.py -> build/lib.linux-x86_64-3.5/ldap
copying Lib/ldap/compat.py -> build/lib.linux-x86_64-3.5/ldap
creating build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/controls/__init__.py -> build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/controls/deref.py -> build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/controls/libldap.py -> build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/controls/openldap.py -> build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/controls/ppolicy.py -> build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/controls/psearch.py -> build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/controls/pwdpolicy.py -> build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/controls/readentry.py -> build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/controls/sessiontrack.py -> build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/controls/simple.py -> build/lib.linux-x86_64-3.5/ldap/controls
copying Lib/ldap/cidict.py -> build/lib.linux-x86_64-3.5/ldap
copying Lib/ldap/dn.py -> build/lib.linux-x86_64-3.5/ldap
creating build/lib.linux-x86_64-3.5/ldap/extop
copying Lib/ldap/extop/__init__.py -> build/lib.linux-x86_64-3.5/ldap/extop
copying Lib/ldap/extop/dds.py -> build/lib.linux-x86_64-3.5/ldap/extop
copying Lib/ldap/filter.py -> build/lib.linux-x86_64-3.5/ldap
copying Lib/ldap/functions.py -> build/lib.linux-x86_64-3.5/ldap
copying Lib/ldap/ldapobject.py -> build/lib.linux-x86_64-3.5/ldap
copying Lib/ldap/logger.py -> build/lib.linux-x86_64-3.5/ldap
copying Lib/ldap/modlist.py -> build/lib.linux-x86_64-3.5/ldap
copying Lib/ldap/resiter.py -> build/lib.linux-x86_64-3.5/ldap
copying Lib/ldap/sasl.py -> build/lib.linux-x86_64-3.5/ldap
creating build/lib.linux-x86_64-3.5/ldap/schema
copying Lib/ldap/schema/__init__.py -> build/lib.linux-x86_64-3.5/ldap/schema
copying Lib/ldap/schema/models.py -> build/lib.linux-x86_64-3.5/ldap/schema
copying Lib/ldap/schema/subentry.py -> build/lib.linux-x86_64-3.5/ldap/schema
copying Lib/ldap/schema/tokenizer.py -> build/lib.linux-x86_64-3.5/ldap/schema
copying Lib/ldap/syncrepl.py -> build/lib.linux-x86_64-3.5/ldap
file Lib/ldap.py (for module ldap) not found
file Lib/ldap/controls.py (for module ldap.controls) not found
file Lib/ldap/extop.py (for module ldap.extop) not found
file Lib/ldap/schema.py (for module ldap.schema) not found
running egg_info
writing requirements to Lib/pyldap.egg-info/requires.txt
writing dependency_links to Lib/pyldap.egg-info/dependency_links.txt
writing Lib/pyldap.egg-info/PKG-INFO
writing top-level names to Lib/pyldap.egg-info/top_level.txt
warning: manifest_maker: standard file '-c' not found

file Lib/ldap.py (for module ldap) not found
file Lib/ldap/controls.py (for module ldap.controls) not found
file Lib/ldap/extop.py (for module ldap.extop) not found
file Lib/ldap/schema.py (for module ldap.schema) not found
reading manifest file 'Lib/pyldap.egg-info/SOURCES.txt'
reading manifest template 'MANIFEST.in'
warning: no files found matching 'Makefile'
warning: no files found matching 'LICENCE'
warning: no files found matching 'Modules/LICENSE'
writing manifest file 'Lib/pyldap.egg-info/SOURCES.txt'
running build_ext
building '_ldap' extension
creating build/temp.linux-x86_64-3.5
creating build/temp.linux-x86_64-3.5/Modules
x86_64-linux-gnu-gcc -pthread -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -g -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -fPIC -DHAVE_SASL -DHAVE_TLS -DHAVE_LIBLDAP_R -DHAVE_LIBLDAP_R -DLDAPMODULE_VERSION=2.4.25.1 -IModules -I/usr/include -I/usr/include/sasl -I/usr/local/include -I/usr/local/include/sasl -I/usr/include/python3.5m -c Modules/LDAPObject.c -o build/temp.linux-x86_64-3.5/Modules/LDAPObject.o
unable to execute 'x86_64-linux-gnu-gcc': No such file or directory
error: command 'x86_64-linux-gnu-gcc' failed with exit status 1

----------------------------------------
Command "/usr/bin/python3 -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-y3r0w2bq/pyldap/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-tctl7av0-record/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /tmp/pip-build-y3r0w2bq/pyldap/