To learn more about the ftplib module, you can query the official documentation: http://docs.python.org/library/ftplib.html
The complete distribution of paramiko comes with many good examples in the GitHub repository: https://github.com/paramiko/paramiko/tree/master/demos
SNMP Link: a collection of SNMP resources: http://www.snmplink.org/
Net-SNMP: SNMP Open Source Tools: http://net-snmp.sourceforge.net/
To learn more about the pysnmp module, you can query the official documentation: http://snmplabs.com/pysnmp/index.html
The Python 3 script to perform LDAP queries and enumerate users, groups, and computers from Windows Domains: https://github.com/m8r0wn/ldap_search
To learn more about the Python ldap module, you can query the official documentation: https://www.python-ldap.org/en/latest/reference/ldap.html
A tutorial and examples for ldap3: https://ldap3.readthedocs.io/tutorial_intro.html