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##### SUMMARY
<!--- Explain the problem briefly below, add suggestions to wording or structure -->
The [PSRP documentation](https://docs.ansible.com/ansible/latest/plugins/connection/psrp.html) mentions `ansible_psrp_connection_backoff` but this seems to be incorrect. The code appears to refer to `ansible_psrp_reconnection_backoff` instead (`reconnection` vs `connection`).
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##### ISSUE TYPE
- Documentation Report

##### COMPONENT NAME
<!--- Write the short name of the rst file, module, plugin, task or feature below, use your best guess if unsure -->
PSRP
lib/ansible/plugins/connection/psrp.py

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.8.0.dev0
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/root/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/local/lib/python2.7/dist-packages/ansible-2.8.0.dev0-py2.7.egg/ansible
  executable location = /usr/local/bin/ansible
  python version = 2.7.15rc1 (default, Nov 12 2018, 14:31:15) [GCC 7.3.0]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
None
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. OS version, browser, etc. -->
Linux, Ubuntu 18.04.2 LTS

##### ADDITIONAL INFORMATION
<!--- Describe how this improves the documentation, e.g. before/after situation or screenshots -->
None.
<!--- HINT: You can paste gist.github.com links for larger files -->
elif self._psrp_read_timeout is not None:
            display.warning("ansible_psrp_read_timeout is unsupported by the current psrp version installed, "
                            "using ansible_psrp_connection_timeout value for read_timeout instead.")
        
        if hasattr(pypsrp, 'FEATURES') and 'wsman_reconnections' in pypsrp.FEATURES:
            self._psrp_conn_kwargs['reconnection_retries'] = self._psrp_reconnection_retries
            self._psrp_conn_kwargs['reconnection_backoff'] = self._psrp_reconnection_backoff
        else:
            if self._psrp_reconnection_retries is not None:
                display.warning("ansible_psrp_reconnection_retries is unsupported by the current psrp version installed.")
            if self._psrp_reconnection_backoff is not None:
                display.warning("ansible_psrp_reconnection_backoff is unsupported by the current psrp version installed.")
        
        for arg in extra_args.intersection(supported_args):
            option = self.get_option('_extras')['ansible_psrp_%s' % arg]
            self._psrp_conn_kwargs[arg] = option
    def _exec_psrp_script(self, script, input_data=None, use_local_scope=True, force_stop=False):
        ps = PowerShell(self.runspace)
        ps.add_script(script, use_local_scope=use_local_scope)
        ps.invoke(input=input_data)
        rc, stdout, stderr = self._parse_pipeline_result(ps)
        if force_stop:
            
            
            
            
            ps.state = PSInvocationState.RUNNING
            ps.stop()
        return rc, stdout, stderr
    def _parse_pipeline_result(self, pipeline):