Update pip_install.rst

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docs/reference/pip_install.rst

@@ -128,6 +128,46 @@ You can also refer to constraints files, like this::
 
     -c some_constraints.txt
 
+.. _`Example Requirements File`:
+
+Example Requirements File
+=========================
+
+Use ``pip install -r dev-requirements.txt`` to install::
+
+    #
+    ####### dev-requirements.txt #######
+    #
+    # Standard installs
+    nose
+    nose-cov
+    beautifulsoup4
+    #
+    ###### Getting Specific Versions ######
+    #   See https://www.python.org/dev/peps/pep-0440/#version-specifiers
+    docopt == 0.6.1             # Version Matching. Must be version 0.6.1
+    keyring >= 4.1.1            # Minimum version 4.1.1
+    coverage != 3.5             # Version Exclusion. Anything except version 3.5
+    Mopidy-Dirble ~= 1.1        # Compatible release. Same as >= 1.1, == 1.1.*
+    #
+    ###### Allowing external and unverified Packages ######
+    #   must explicitly tell pip which packages are external and unverified.
+    #   CMD line equivalent: 'pip install pyPdf --allow-external pyPdf --allow-unverified pyPdf'
+    --allow-external pyPdf
+    --allow-unverified pyPdf
+    pyPdf
+    #
+    ###### Refer to other requirements files ######
+    -r other-requirements.txt
+    #
+    ###### Other standard installs ######
+    rejected
+    green
+    #
+    ###### a particular file ######
+    ./downloads/numpy-1.9.2-cp34-none-win32.whl
+    http://wxpython.org/Phoenix/snapshot-builds/wxPython_Phoenix-3.0.3.dev1820+49a8884-cp34-none-win_amd64.whl
+
 .. _`Requirement Specifiers`:
 
 Requirement Specifiers