Looping through cisco switch ports

Question

I am new to Network automation with python and am writing a code to telnet to a switch and check for port security.The problem is with the loop as it skips the first interface as shown in the code and result.

import telnetlib

pool = ["10.1.1.1","10.1.1.2"]
user = "admin"`
password = "admin"`

for IP in pool:
 print(f"Checking Switch --> {IP}")
 tn = telnetlib.Telnet(IP)
 tn.read_until(b"Username: ")
 tn.write(user.encode('ascii') + b"\n")
 if password:
  tn.read_until(b"Password: ")
  tn.write(password.encode('ascii') + b"\n")
  for port in range(1,4):
  print(f"checking port :{port}")
  tn.write(f"show port-security interface fastethernet0/{port}\n".encode('ascii'))
  output = tn.read_until(b"#").decode('ascii')
  print(output)

RESULT:

Checking Switch --> 10.1.1.1
checking port :1

Post-4th-lab-2#
checking port :2
show port-security interface fastethernet0/1
Port Security              : Enabled
Port Status                : Secure-down
Violation Mode             : Shutdown
Aging Time                 : 0 mins
Aging Type                 : Absolute
SecureStatic Address Aging : Disabled
Maximum MAC Addresses      : 1
Total MAC Addresses        : 1
Configured MAC Addresses   : 0
Sticky MAC Addresses       : 1
Last Source Address:Vlan   : 0000.0000.0000:0
Security Violation Count   : 0

Post-4th-lab-2#
checking port :3
show port-security interface fastethernet0/2
Port Security              : Enabled
Port Status                : Secure-down
Violation Mode             : Shutdown
Aging Time                 : 0 mins
Aging Type                 : Absolute
SecureStatic Address Aging : Disabled
Maximum MAC Addresses      : 1
Total MAC Addresses        : 1
Configured MAC Addresses   : 0
Sticky MAC Addresses       : 1
Last Source Address:Vlan   : 0000.0000.0000:0
Security Violation Count   : 0