rosrun tab completion not working and find: ‘’: Datei oder Verzeichnis nicht gefunden

edit

I just installed ROS-Noetic from source on a raspberry pi 3B+ with raspbian stretch. I have some strange problems regarding rosrun. The first problem that i have is that the tab completion is not working. I did source ./devel/setup.bash but it does not work.

Before that i had the following problem:

TKI@pi:~/ROS_Calculate/catkin_ws $ rosrun caterminate called after throwing an instance of 
'rospack::Exception'
what():  error parsing manifest of package rosmaster at /opt/ros/melodic/share/rosmaster/package.xml

Which i hopefully fixed according to this rosanswers question

My ROS_PACKAGE_PATH looks like this after i source ./devel/setup.bash of my catkin workspace:

TKI@pi:~/ROS_Calculate/catkin_ws $ echo $ROS_PACKAGE_PATH
/home/TKI/ROS_Calculate/catkin_ws/src:/opt/ros/noetic/share

The other problem that i have with rosrun is that it says:

find: ‘’: Datei oder Verzeichnis nicht gefunden

after i start my ros node with rosrun.

TKI@pi:~/ROS_Calculate/catkin_ws $ rosrun calculate calc_talker.py
find: ‘’: Datei oder Verzeichnis nicht gefunden
[INFO] [1614837047.381706]: first_number: 1
second_number: 1
[INFO] [1614837047.481842]: first_number: 2
second_number: 1
[INFO] [1614837047.581801]: first_number: 3
second_number: 2

I am still pretty new to ROS and i do not know how to solve this. I am very very gratefull for your help!

Edit - The package.xml and calc_talker.py for my calculate package looks like this:

<?xml version="1.0"?>
<package format="2">
    <name>calculate</name>
    <version>0.0.1</version>
    <description>
        The calculate package is a small package to train ROS programming.
        It consists of a calc_talker that calculates the fibonacci sequence
        and a calc_listener that is listening to the calc_talkers calculations.
        The package also defines a custom message Calc.
    </description>
    <maintainer email="email@email.de">mab0189</maintainer>
    <license>BSD</license>
    <author email="email@email.de">mab0189</author>
    <buildtool_depend>catkin</buildtool_depend>
    <build_depend>rospy</build_depend>
    <build_export_depend>rospy</build_export_depend>
    <exec_depend>rospy</exec_depend>
    <build_depend>message_generation</build_depend>
    <exec_depend>message_runtime</exec_depend>
</package>

calc_talker.py:

#!/usr/bin/env python

import rospy
from calculate.msg import Calc

def talker():

    pub = rospy.Publisher("Calc_Chatter", Calc, queue_size=100)
    rospy.init_node("Calc_Talker", anonymous=True)
    rate = rospy.Rate(10)

    number1 = 1
    number2 = 1

    while not rospy.is_shutdown():

        result = number1 + number2

        msg = Calc()
        msg.first_number = number1
        msg.second_number = number2

        number2 = number1
        number1 = result

        rospy.loginfo(msg)
        pub.publish(msg)
        rate.sleep()

if __name__ == "__main__":
    try:
        talker()
    except rospy.ROSInterruptException:
        pass
#EoF