diff --git a/doc/dev-guides/writing-python-agents.md b/doc/dev-guides/writing-python-agents.md
index 1b87e753a..f26313ff8 100644
--- a/doc/dev-guides/writing-python-agents.md
+++ b/doc/dev-guides/writing-python-agents.md
@@ -1,90 +1,90 @@
 # Resource Agent guide for Python
 
 ## Introduction
 
 A simple library for authoring resource agents in Python is
 provided in the `ocf.py` library.
 
 Agents written in Python should be ideally compatible both with Python
 2.7+ and Python 3.3+.
 
 The library provides various helper constants and functions, a logging
 implementation as well as a run loop and metadata generation facility.
 
 ## Constants
 
 The following OCF constants are provided:
 
 * `OCF_SUCCESS`
 * `OCF_ERR_GENERIC`
 * `OCF_ERR_ARGS`
 * `OCF_ERR_UNIMPLEMENTED`
 * `OCF_ERR_PERM`
 * `OCF_ERR_INSTALLED`
 * `OCF_ERR_CONFIGURED`
 * `OCF_NOT_RUNNING`
 * `OCF_RUNNING_MASTER`
 * `OCF_FAILED_MASTER`
 * `OCF_RESOURCE_INSTANCE`
 * `HA_DEBUG`
 * `HA_DATEFMT`
 * `HA_LOGFACILITY`
 * `HA_LOGFILE`
 * `HA_DEBUGLOG`
 * `OCF_ACTION` -- Set to `$__OCF_ACTION` if set, or to the first command line argument.
 
 ## Logger
 
 The `logger` variable holds a Python standard log object with its
 formatter set to follow the OCF standard logging format.
 
 Example:
 
 ``` python
 
 from ocf import logger
 
 logger.error("Something went terribly wrong.")
 
 ```
 
 ## Helper functions
 
 * `ocf_exit_reason`: Prints the exit error string to stderr.
 * `have_binary`: Returns True if the given binary is available.
 * `is_true`: Converts an OCF truth value to a Python boolean.
 * `get_parameter`: Looks up the matching `OCF_RESKEY_` environment variable.
 * `Agent`: Class which helps to generate the XML metadata.
 * `run`: OCF run loop implementation.
 
 ## Run loop and metadata example
 
 ``` python
 import os
 import sys
 
-OCF_FUNCTIONS_DIR="%s/lib/heartbeat" % os.environ.get("OCF_ROOT")
+OCF_FUNCTIONS_DIR = os.environ.get("OCF_FUNCTIONS_DIR", "%s/lib/heartbeat" % os.environ.get("OCF_ROOT"))
 sys.path.append(OCF_FUNCTIONS_DIR)
 import ocf
 
 def start_action(argument):
     print("The start action receives the argument as a parameter: {}".format(argument))
 
 
 def main():
     agent = ocf.Agent("example-agent",
                       shortdesc="This is an example agent",
                       longdesc="An example of how to " +
                       "write an agent in Python using the ocf " +
                       "Python library.")
     agent.add_parameter("argument",
                         shortdesc="Example argument",
                         longdesc="This argument is just an example.",
                         content_type="string",
                         default="foobar")
     agent.add_action("start", timeout=60, handler=start_action)
     agent.run()
 
 if __name__ == "__main__":
     main()
 ```